The Nature and IVs can indeed be SR'd, so I wish you luck! Or well, I hope it went well if you did it already! ^-^
And about the rules, I'm not scolding you, and it's not worth an infraction so don't worry. Just remember Keiran and I are here to answer your questions about them!
My suggestion would be to make a second thread with the prefix Shiny, only for your Shiny Oshawott, to look for good offers. When you use the Giveaway prefix, it's a bit like Wonder Trading your Pokémon ; you will get mostly random Pikipek, but sometimes you may get a really cool Pokémon, and those are usually referred as "Tips". While you may say something along the lines of "tip isn't required but I like rareball breedjects" you cannot ask people for offers on your Giveaway thread. If the rule is unclear on our rule thread, just let me know and I'll correct it.