Yes, Simon was quite the handful when he first got here. I had to buy chew toys for him and chew proof the house - it was like having a rabbit all over again! He's settled down quite a bit, but he can still get into trouble if we miss something that's on his "irresistible list".
Purrl had to wear a collar when we first brought her home . She was about a year old and she'd sneak up on a shy older calico and want to rough house. The calico got very leery and skittish, so we belled Purrl to give the calico a warning.
So, no problems with a collar - I'm sure she'd re-acclimate to it. Especially if she knew it was a food ticket! However, that is the issue. I don't see on those chip feeders that I can set a time for it to be available. If she knows she can eat at will, she'll clean the bowl as soon as it's available, therefore defeating the purpose of a little nibble about 2 or 3 am. It might work if I can plug it into a wall timer or some such so it will turn on about 2am and then be available to her.
I'm still thinking on a workable solution to this, to avoid having to shut her in a room overnight. Only one of the 3 will stand for being shut out or shut in and Purrl isn't that one.
For the time-being, hubby will get up at 4 and give her a little snack. She doesn't get AMPS-feed-shoot until 6:30 am. I'm hoping until we find a nicer solution that this will cure the hour before feeding water barfs.