I'm sorry for your loss.

These frogs are not very active. They are nocturnal and Occationally love around at night. If the frog is consistently jumping against the glass, something is wrong. This is usually stress behavior. Sometimes you may have one that does this when hungry, but it isn't normal behavior of a stress free animal.

You said the substraight was a peat moss mix. Might I inquire on what the full bedding mix is and when the last time you can recall the frog deficating?

They can suddenly die from forms of illness that are not externally visible.