And seeing it was on a no interest credit card I think of it as just borrowing money, not going into bad debt. 

Until he got the restriction lifted a little bit the only thing he had to live on was a borrowed credit card from a relative.

For the bottom of the commercial market, properties not deemed worthy of Loopnet, a lot of driving around, using Cagis or similar GIS databases to get owners' name and addresses, and putting notes and business cards in doors is an alternative to Loopnet (I don't know about Crexi).

Financed the rehab with zero percent interest credit card How did you add value to the deal?

They have study guides, practice exams, flash cards, and much more.

He does have an ITIN number, recently opened up an Amex card in the States to start building credit history, and has an LLC and a US address.

They have excellent payment history, and their credit can be explained with a history of opening several credit cards and a brief period during covid with a few missed payments.  

Some lenders can do foreign nationals, but most are able to lend to green cards and most visa-type holders.

There is a reason credit card rates are 20-30%... 

Work out a payment plan, put it in on a credit card, but get the thing replaced!