Hi again, if the monitor has been removed for spot cleaning he`s been handled! (Not being sarcastic), that might be enough for him to regurgitate the food, especially as he will undoubtably be stressed just now (new surroundings, etc).
I always think it`s better to be safe than sorry, if you could get a fecal check done it wouldn`t hurt, and get the vet to take a look at the monitor.