Good hints, but these events likely were not very relevant.
While Lemmy gained almost 200,000 new users in the last two days, the active users increased by less than 3,000, just about the same as pretty much every two-day period recently. So pretty much all of those new users are inactive. That's not hordes of Redditors coming over and exploring Lemmy, that's hordes of bot and sleeper accounts being created.

https://lemmy.fediverse.observer/dailystats