Hope I can test yours! I have a small spot too.
...and cleaned these horrible burns/dirty spots on the headliner also from the PO. I bought a bunch of AMMO NYC stuff as a non-believer, but WOW am I convinced. Larry's stuff is bomb.
First picture before, largest thing is like a fingernail size.
Second, after AMMO Shag sat for a bit. Honestly I don't even think I needed to agitate beforehand, though I did, it lifted everything out and I just wiped it off. Crazy.
Last, after. No weird stains left over, no discoloration from the product. 10/10 would use again. Also pulled some stains from my visors!