I guess it's a way of them wanting to control ?
That's what I think it was. She wasn't in control of the situation (ours was moving her to her BGB and she had a hard time--yours is not getting to go your room and having to sleep independently again, etc.) so she found something to be in control of. I think you're absolutely right.
Also, I forgot to mention. You might need to make some clear cut "rules" about what will and will NOT happen when she wakes at night. You can talk to her about it during the day to prepare her. "Remember, now that you're feeling better, mommy and daddy aren't going to get you drinks at night anymore." or "You're such a big girl and you can fall back to sleep by yourself. Mommy will check on you, but you are in charge of going to sleep again by yourself." Then stick with it. If you say no drinks, then no drinks. If you say no blanket retucking in etc. then don't retuck. ESPECIALLY if she's capable of doing those things herself. After awhile she won't be "rewarded" for calling you in as you'll be a pretty dull experience for her at night if you don't make a big to do about it and she'll have no reason to stay awake until you come and will learn to put herself back to sleep as she used to do.
Also, not sure if she has one already or not, but my DD really likes having a night light. She is less disoriented when she does wake and can usually resettle herself back to sleep. That may help (although keep it dim or it could disturb her sleep if it's too bright). We also play music, not sure if that would be comforting to her or not.