I know this is 2.5 weeks later, but on the 'gacha' subject, it was probably 'rebagacha' which has nothing to do with the games where you collect a bunch of characters by rolling for a low random chance at a higher rarity.
To my understanding, it comes from 'lever' (or control stick, like you would see on an arcade cabinet, but also modern video game controllers, which becomes 'reba' in katakana) and 'gacha' as a sound effect for something rattling around (which is the same root as where it comes from for gacha games, except in that case, it hearkens back to physical gacha machines where you insert a coin and get a random plastic capsule).
In other words, 'rebagacha' ultimately just means shaking the control stick like crazy to the point it makes a bunch of noise - or in more common English parlance, the intended effect is 'button mashing'. Random chance need not be a factor, and in fact just having to do something quickly or X times within a Y time frame was pretty common for how this worked in older games like this.