Need coparenting advice

So this year is my daughters dads year for Christmas with our little one. She’s 4. He’s texted me regarding their itinerary and says he’s got a lot planned with her and he’s excited to spend one on one time with her. Now all of a sudden the location and duration of the trip has changed. I agreed just due to the fact that it’s his year and he seemed very excited to take her somewhere different that what was initially discussed. However, I spoke with one of his family members and they spilled the beans that his girlfriend is accompanying him on this trip as well as her family. I’ve never met them (girlfriend included), and now I’m a little confused on how to approach the situation as he has still yet to even let me know that they are all going on this trip. I’m concerned one because I don’t know this woman and her family, and two because I haven’t even been given the courtesy of saying “hey I know you haven’t met her but ...”

We don’t have a typical custody agreement as he is currently stationed overseas and has only seen her once in the last year because if that. On top of that I found out he came back to the states a few months ago and was IN THE SAME STATE but didn’t call or ask to see our child.

I’m really at a loss on how to approach the situation as I am concerned that he will become defensive and manipulate the situation to make it appear that I’m the unreasonable one. Am I?