Professional tenants are good and you need to be checking the court records, etc, even after running an automated screening.  

If they break, without my approval, and I take to court, I’m assuming I’d win, but how hard is it to collect after court ruling?

The only option I see is to try to ease some of the tension, get them back to paying the original amount until courts open again where eviction is back on table. 

He said something about 75% was doable but would most likely require some court arguments. 90% was sure fire.

Learn to make a layup before trying to beat LeBron James on the court, in other words.Good luck out there!

Wondering if I could just pay the Recorders Office or put the money in escrow with Clerk of Courts?

Wholesaling in many states - including mine - is considered the unlicensed practice of real estate and it comes with a whole lot of bad: "Unlicensed practice of real estate is a third-degree felony punishable in criminal court, for each violation, by up to five years in prison and $5,000 in fines."

@Patrick Reagan  Something else that wasn't mentioned is that, in many jurisdictions, courts have ruled that landlords can't collect or even request rent from a tenant in an "illegal" unit. 

I mean, sure you "could" but your legally well outside of the lines so if you ever have an issue with either tenant and need to evict, and tenant brings that up in court, it's gonna bite you in the butt. 

My attorney told me that because the contract is with a unlicensed contractor and I was never alerted of any subcontractors that even if the subcontractors put a lien on my property it can be removed in court easily.