OH i found it! how, you ask? simply by reading the other newsposts around the joogle one, finding one i posted that mentioned giving up on advent of code, checking what day i abandoned it on, looking for videos that chess uploaded around that time, narrowing it down to the ones that i know i watched, and fast forwarding through the most likely candidates until i found the exact part i was looking for, this level of reasoning is possible for erika furudo.

here's the link (timestamps in embeds apparently don't work since the forums upgrade so skip to 41:10)