>Haha good call. I’ve started a discourse with them now and they said that they’ll decide whether to cite my paper once both have been accepted somewhere and whether they like some of the video results I can show them. Promising stuff at least!

yup! Academia and research is really about the collaborations that get formed rather than one project. This might be more helpful to you than if it had not happened. Good luck!

you might want to mention how excited you are that a fancy lab like theirs is working on similar stuff ... maybe you can give them a talk or something :)

these are concurrent works, the first to put on arxiv by a few days is not the one that gets bragging rights :) One thing you could do is send them your arxiv link, tell them it's concurrent work, and in the next arxiv iteration or whatever you should each cite eachother as concurrent work.