Nothing I've read indicates that's the case, just that the fine increases by $87,502 per day, which is just over $2.6 million per 30 days.
"On the 9 percent interest, Trump is being charged an additional $87,502 per day from February 16, according to Associated Press calculations. That means Trump will have to pay $1,050,024 for the 12 days between February 16 and Wednesday, February 28."
Donald Trump Will Owe $1 Million in Interest on Fine Within Days (newsweek.com)
If it was compounding then you'd expect the daily amount to already have gone up.
He can stop the clock, at least until the appeal is over, by posting the full amount as a bond, but if he has to borrow the money he'll be paying interest on that too.
A GoFundMe page opened for him has collected almost $700,000 for the cause. Not even keeping up with the interest owing, let alone paying off the fine.
"Now some of Trump's supporters are donating specifically to help pay his $355 million fraud judgment, via a GoFundMe page created by Elena Cardone, the wife of investor Grant Cardone.
As of Tuesday afternoon, the fundraiser had pocketed nearly $700,000 — and had also sparked backlash on social media. GoFundMe responded to those calls on Monday by saying the fundraiser is "within our terms of service.""
How will Trump pay legal penalties in fraud, Carroll cases? : NPR
And people here complain about road accident victims raising money on the platform.