I hope all go well with him/her....
Ammonia isn't the only level you have to worry about.
How are your Nitrates, Nitrites, pH, Alkilinity, and temp?
Anyone of these can cause him/her to try and escape besides ust being curious.
If you can, try and lower your water level to the point where they can't climb out.
I hope these all help and good luck with the recovery.