I sort of do something similar to the “mark as correct” approach - I use the WaniKani Doublecheck user script mentioned above and usually I’ll try two or three times to get it correct if I think I do know it. I’ve had times where it took enough tries that I ended up intentionally letting it be a fail, but if it’s a case where I fat-finger something or forget the extra n when typing out something that has an ん followed by a vowel (I’ve seen accidental にs a lot recently) and get it right, I feel like I knew it.
But I get the frustration aspect and all I can say is just remember that this is a long journey, and this is a part of it. I think the mistakes are sometimes more valuable than getting something correct because you happened to remember that 350% of the kanji at the level you’re working on are し for a totally made-up example. 