AITA for telling my kids dad that if he wants to make bedtime difficult, our daughter will only sleep at his house

AITA for telling my kids dad that if he wants to make bedtime difficult, our daughter will only sleep at his house

My ex, Matt, and I have 3 daughters, Zoey (10), Kenzie (6), and Paige (5). We share 50/50 custody of the girls. 3 years ago, he married Julie.

Kenzie is autistic with very high support needs. She has a 1-1 aide at school and receives speech and OT services multiple times a week.

It is nearly impossible to get Kenzie to sleep. She likes small, tight spaces so she still has a toddler bed, even though she’s clearly growing out of it, she needs to be tucked in so tight that I don’t think she can move, then she needs her weighted blanket on top of that, then her fluffy blanket, then all of her stuffies need to get in the bed with her. Then we read the same 3 stories, turn on the night light, and turn on her sound machine, which just plays twinkle twinkle little star instrumental all night. Her entire routine takes at least an hour from the time I get her in bed.

Matt got tired of Kenzies bedtime routine so he started putting Kenzie in his bed between him and Julie. I only found out when Kenzie refused to get in her bed at my house. I gave in because if Kenzie doesn’t sleep, nobody sleeps, and it’s just ridiculous. They‘re giving her warm milk before bed, which means we’re back in pull ups at night. She also only sleeps with her head buried in my chest and when I brought it up to Matt, Julie just laughed and said “yeah, she’s been doing that here too”. Then we do 1 book, I’m supposed to pat her back, and she’s out. It’s much faster but I’m not putting her in my bed every night.

I tried talking to Matt about this being unsustainable but he‘s refusing to go back to her old routine so I told him that Kenzie will only be sleeping at his house until they get her to sleep in her own bed.

Matt thinks I’m being unreasonable because he and Julie deserve a break but he caused this so he can fix it. I still visit Kenzie for a few hours a day but I’ve made it very clear that she’s not going back to my house until she sleeps in her own bed.

Now Matt and Julie are accusing me of abandoning my child because she’s disabled and have spread the narrative that I’m a horrible mother. AITA for not letting her come back until she sleeps in her own bed?