I wish I could help you with an answer, but I really don't know what is safe for sugar gliders. Hopefully someone with experience will see this and have an answer for you.
You will need temporary caging for them either way, so you might want to check into a suitable temporary enclosure asap so you can get them out of the rusty cage while you find solution and repair safely.
If you do not have a temporary enclosure already probably the best would be to go get a pop-up dog kennel in the meantime. You can get one big enough for them to use and then it can be stored more easily afterward.