I fear them withholding random fees mentioned above and in general failing to hand-off any leases/notices/payments to the incoming property manager. 

If they were section 8 previously the standard of care for the landlord to get rent payment and the standard of care for what might be found in a typical rental are different.Section 8 you get inspections and the inspector can be overzealous with demands and withhold the rent payment until in compliance.

In your previous dealing has the title company handeled the tax withholding or was that done in some other manner?

However due to a work related injury, I'm currently on FMLA at my job only receiving 66% of my regular income without tax withholding until at least April 2019.  

A lot of agents withhold the sales price along with other information.

If you could provide the ARV of these properties, along with the respective monthly fees associated with holding each property then we'd be getting closer to which looks like a more favorable rental.

Do the owners withhold rent rolls, or are they avoiding the actual #s because the properties need significant rehab?

In fact there are few other things to consider when investing in the US as foreigner, one of them is the withholding taxes.  

I can withhold any future feedback on design choices if you like.

But I'd rather be Captain Obvious than withhold something that you might find helpful.