The pH isn't troubling at all, the Ammonia and Nitrite is the main issue at hand. From the readings I saw in your first picture it seems to indicate a dangerous level of those toxins for your fish.
I would recommend a 50-75% water change, but hopefully someone else will chime in.
If you are dosing the tank with prime it could protect the fish for a time. A regular dose of Prime should probably make it safe for a time, but I'm not sure how long it lasts.
The way that I have cycled tanks with fish is by testing the ammonia and nitrite daily. If either reads over 0.25 I do water changes until it reads 0.25 or less.
Again, I hope some other people chime in. I really like your oscars by the way, I've always wanted one but my girlfriend doesn't like them.