So there. There might be better scenarios, but that's what I could come up with.
Please be aware that I'm neither a native English speaker nor a teacher.
I see what you're getting at but I can't quite imagine what this member of staff is going to check for in the cloakroom. When he/she walks into the cloakroom it won't be possible to tell of anything has already gone missing/been lost and, unless you expect him/her to stay in the cloakroom for the rest of the evening, it won't be possible to check that nothing gets lost before the end of the party.
Remember - if you don't use correct capitalisation, punctuation and spacing, anything you write will be incorrect.