Believe it or not I did read it. Your first paragraph is what was addressed said simply "If it's an accidental kiss won't tag as incest " This comes across as commenting, quite clearly, that the incest tag may be needed if the kiss was not accidental. There was no "what if" scenario here. As such, I provided you the information related to that comment related to tags.You are the one who are not reading, read what I said again, "WHAT IF"
As to your "what if" scenario on the rest of the post, my reply was not responding to that as it's a non-canon scenario you cooked up. Nothing wrong with that, and a lot of that goes on in here, and no issues with it at all.