A napkin with a map to a pizza restaurant drawn on it or perhaps a napkin from a restaurant with a map on it to somewhere else. Both of those are completely believable, mundane and likely answers to that email referencing a pizza related map on a handkerchief.

It amounts to basically asking if they can throw out a note they found or if it is still needed.

Dominoes on cheese referred to playing dominoes while under the effects of cheese. This email actually made me laugh when I read it. It appears to be a tongue in cheek remark about his plan to literally eat cheese and play dominoes that evening.

Are you on the autistic or asperger spectrum by any chance? I'm being serious and mean no offense by that. It's hard to do with text but I think many people misinterpreting the emails may have trouble with inflection and understanding sarcasm.