So a little update for those who find this thread and have the same issue.
After a few days of dosing the stability to the letter in the directions my tank has finished the mini cycle.
The ammonia was 0-0.25 ppm (might just be 0 my eyes can't see the colors very well) less then 24 hours after my last ammonia update, and my nitrites were 0 when I tested the other day.
The plants killed all of the misc green algae in just a couple days since I posted last and all that's left is the dreaded staghorn algae, however it has stopped spreading and only what was present with the ammonia spike is growing bigger so that's good.
I've been spot treating it with H2O2 and I'm just going to continue doing that a little bit every day until it's gone, so far every day a few tufts out of the whole lot that I've spot treated turn red (might be old hydrogen peroxide no idea TBH) so it might take a little bit for it to be all killed.