Option 2, personally I know how annoying it is for DH to say no I don't want to as I don't know anyone suck it up princess LOL
I think he is way to young to leave at a party with people you don't know and he is not old enough to not need someone watching what he is doing. No way would I drop my 3 year old off at a party as the host will be way to busy to watch over him, unless you know someone else at party that you can ask to watch him.

Good luck (Go to your workshop and enjoy)