Thanks again for the helpful advice! I will tell my partner and the pet sitter just to talk to him outside then. I was just worried that he would get used to no one ever invading his cage with their hands and would freak out if I tried in a few weeks while right now he's used to it.
The pet sitter is coming to my place, I was thinking of boarding him at the bird store I bought him at but I was worried it would be too traumatic for him after finally getting used to our house so I searched for a long time for a pet sitter with experience with budgies. I had to move him up to our bedroom temporarily while we were having a BBQ on the weekend and the poor baby was super stressed so I imagine it would be super traumatic for him to be moved somewhere completely different!
Here's my instructions for the pet sitter, I tried to cover everything! I'm really going to miss him while I'm gone

I'm not sure how long budgie's memories are and I hope he doesn't forget me while I'm gone since he'll only have known me for two weeks at that point.
Thanks again for the advice!