Even if there were meant to be 190 Pokemon in Gen I, I'm not exactly sold that those specific Pokemon were the ones meant to be in the Gen I games. It appears the way they programmed the Pokemon into Gen I was to insert each individual Pokemon in as they made them, probably to see how/if their ideas worked on a Game Boy. Who knows what happened to the 39 that got removed (if they aren't the Gen II Pokemon), but perhaps their idea or design just didn't work out when churned through into the GB graphics.
The main reason I believe the Gen II Pokemon aren't leftover from Gen I is because of the order. Other than Ho-oh being after Heracross, the order is a direct copy-paste of #212-#249 in the National Pokedex, starting with Scizor and ending with Lugia. That tells me that for Gen II, the Pokemon were all planned out/already made and inserted in in the order of the Pokedex. Along the way, somebody remembered the 39 empty Pokedex slots from Gen I, and they played some fill-in-the-blank to get all 251 Pokemon in before hitting 256 Pokemon indexes
(Fun fact: Forcing a Gen II game to register 256 Pokemon seen/owned will made the number overflow and reset to 0, as seen in the linked video).
I don't think that those glitch Gen I Pokemon turn into actual Pokemon in Gen II because they were meant to be in Gen I, but because their hexadecimal ID numbers just happen to be the same (because they exist and are assigned to something in Gen II).