Wow, you’re right. I didn’t notice he learns water gun twice until now.
I’m making another Picodex that includes gen 2. So it will be fixed in that one. I think I’ll also combine the best base stats of the yellow and red version missingnos to make it better.
The Yellow version missingno also learns payday & bind. And the M(00) pokemon learns pound. So I can include those moves too.
(Source: https://bulbapedia.bulbagarden.net/wiki/MissingNo.#Base_stats)