I know what you are experiencing and it is hard to not stress.
We were away for three weeks and had a family member come and stay whilst we were away. I typed out explicit instructions, left vet's phone number, made sure enough food was available , wrote what other fresh green food to buy and more or less wrote out a daily schedule. Some may think we were overly cautious, but that is how we feel about our birds.
I am lucky in the fact the birds knew and have interacted regularly with my step son as well.
I hope you enjoy your holiday, make sure the person knows and realises that the seed leaves husks behind, I told My son to change the seed regardless of amount in the feed cup every second day to be on the safe side.