For the karaoke one say that you don’t do karaoke even in a good year so you’re certainly not going to inflict that torture on yourself or others in this of all years but instead you’ve chose a nice YouTube /tiktok/etc of kittens/classic great song/appalling rendition of bad song by someone else/ something you think they’d love or hate, then play it on your phone and hold it up in front of your camera so they can see it and your hand holding it but not much else, bonus points for jiggling it around a bit to make it difficult to watch and hear. Hopefully they will soon get you to stop.
If they try to get you to do something in person tell them that it’s supposed to be a party and they’re not allowed to be mean and bully you at a party, you’ve made an effort, they are causing a fuss and being miserable and embarrassing everybody. So stop bullying me and go pick on somebody else. If you can get them words out about them being mean, miserable, bullying, etc first, they’ll need to be really careful as you can easily then go to HR and say that you repeatedly asked them to leave you alone, to stop bullying you and just move on butthey repeatedly didn’t it’s not going to reflect well on them.
Forthr boss who expects you to go to her house, ring up and say that you can’t see a parking spot so you turned around and have come home again. Or ask her to provide a parking pass in advance s you can’t ever find parking, then just say it never turned up so you assumed her plans had changed and she didn’t want you going. Or say that you thought she was joking as it obviously wasn’t a work meeting and it’s too cold to stand around outside at the moment.