Need help with baby sleep

My 10 month old still won't sleep through the night even after sleep training. He wakes up every 2 to 3 hours and only wants me to comfort him. I kind of know how to stop this, but in about a week I have a Christmas work event to go to with my husband and not sure what to do if he were to wake up and I'm not home.

I'm afraid he won't take a bottle from my MIL and want to be soothed back to sleep by her.

Any tips?? I really want to try to go to this event for a bit, since my husband and I really never go out