I don't know what to do😥

Me and my husband recently became foster parents because we really want to make a difference. We have a little boy who came to us last week and everyday he's been bawling that he wants his mom. It's heart breaking crying. I talked to his caseworker about his mom and if we can set up visitations because he's obviously really hurt, but she says right now mom has no visitation rights. He will cry all night saying "I want mama! I don't anat you I want mama!" Its been like this for over a week and it hurts so much. From what I know about the situation he was taken away over allegations and honestly with how he's acting I feel like the allegations against his mom aren't true because this kid seems traumatized from being taken away from his mom, not anything else, but idk if I'm allowed to communicate with her since she doesn't have visitation rights yet. Idk what to do to help him.😥😥😥

Edit: I never said I was going to contact her. I know that's a against the rules and I would never put him in harms way. The only reason I question allegations is because I was taken away from my mom based on allegations that were in no way true. I would never contact him mom without permission. Just wanting to know how I can help him adjust without her.