Could this hold up in a legal standpoint?? Any advice is appreciated

Could something like this actually hold up in court ? Has anyone here went through the process of losing a family member and have any knowledge as to what the legal process is afterwards for blood relatives ? Any tips or advice would be appreciated. My grandmother passed away a few months ago. I do know that she had a will at one point but apparently it has not been found at this time nobody knows what happened to it or what she did with it. She does have a power of attorney who was appointed not long before her death, this person is not a relative (she told us she was) but turns out shes just an old friend she worked with years and years back. This person as her POA has a lot of legal control over certain things and I’m just not really sure where I or my siblings as her grandchildren stand in everything because she does not communicate regularly or clearly with me or other family members about what is going on. She does not let us go to our grandmothers house she says we are not “allowed” to go over there or be there look through any personal belongings etc unless she is present. There is a man who lived with my grandmother they were just friends he lost his home and she let him have a bedroom there, we have known him since we were small children he still currently resides in the house by himself but also does not communicate with anyone. The one time one of us went over there he was acting very strange, making very perverted comments talking about when we were little talking about our butts and how he’s in love with my sister and has been since she was little etc just overall very uncomfortable to deal with and not allowing stuff to be gone through not allowing personal belongings of our grandmothers to be taken etc. He has also TRASHED the house it’s in terrible condition since her passing. Her POA has said that he’s moving to another state to be in a nursing home somewhere and has been saying that for a while but it’s yet to happen. When we start questioning her she basically gives answers in riddles she beats around the bush and is very vague and restricts how much info she shares with us. If we start asking too many questions she ghosts us and will ignore phone calls, ignore text messages for weeks on end, and won’t meet up in person to discuss anything. We have so many questions but just aren’t comfortable asking her because we don’t want her to shut us out and keep us in the dark, there is a guardian ad litem but she will not give us her name or contact info. There was a court date not long following her passing and in the paperwork it was stated that IF the will is not found then all assets will go to first of kin which is me and my siblings. All other family members have passed away we are the only ones left. However this POA as of this week told one of us that she found a “letter” at our grandmothers house. She said she was over there going through all her papers and stuff and shredding documents, said she shredded the custody paperwork showing that our grandmother had custody of me and my siblings as children and raised us, I find that odd that she would shred something like that or be shredding things in the first place. She said this letter she found is not in hand writing it was typed out on a computer and printed out there is no signature it has not been notarized nothing like that, just a piece of paper with computer typing on it she would not even show us this letter she would not let us read it nothing. All she said about what was included in this letter is that it appeared to be our grandmothers wishes about what she wants done with her property and assets etc following her death, she said it was typed in big bold letters that 70% of EVERYTHING go to this man that is still living in the house, she said that me and my siblings names were mentioned in the letter somewhere but then quickly changed the subject she did not entail how we were mentioned or surrounding what. She did not say anything about the remaining 30% which I personally do not believe my grandmother would have typed that out. She was suffering from dementia as well as Alzheimer’s for many many years, she couldn’t even remember who any of us were in the end I highly doubt she was on a computer typing things up and printing them out. My grandmother always said she wanted 100% of all assets to be sold and the money be dived between me, my siblings, and the great grandchildren. Her POA however seems to believe this letter was actually typed out by my grandmother so I’m not really sure what she plans on doing with it or if this man could actually get 70% of all of my grandmothers things. She said she took the letter from the house and that the man who lives there keeps asking her where it went and seems upset that it’s gone. Could a typed up note like that even hold up in a legal standpoint with it not being in handwriting and having no signature ? Like there is no proof that my grandmother typed that up. Anyone could have typed that out for all we know this man who lives in the house could have typed that up and put it somewhere where it would be found or something. I just feel like since the will has not been found that he or they are taking advantage of that and grasping at straws and possibly fabricating things to go in their favor idk. I just don’t trust it and don’t trust him and don’t trust her POA. How could I go about getting in touch with someone legally to be more involved and kinda explain everything and what’s supposed to happen etc as it’s happening ? I would just be a lot more comfortable if I was being kept in the loop regularly and could ask my questions to someone legally instead of having to rely on her shallow once in a blue moon updates and running her off when we ask too many questions that she doesn’t like. I just feel like everyone is being sneaky about all of this and doing things behind closed doors to benefit themselves and this is not what my grandmother would have wanted.