*sigh* this is a dead horse that will never stop getting beaten the "proper fiat/wallet purchase implementation" that you speak of is, at this moment, IMPOSSIBLE to achieve since it requires SEVERAL HUNDRED THOUSAND AMERICAN DOLLARS to get LICENSED by FINCen to enable this. SOOOO either drop it or cough up the couple hundred thousand dollars needed to achieve this....
i dont know about that exactly. there may be other ways. as someone who has worked in the Point of Sale industry for years it's not impossible to get coding done that implements credit/debitcard to a cryptocurrency. i actually know devs who are capable of making this happen with full integration for barcode systems at checkout counters etc. since cryptocurrencies are considered a commodity it's much like buying a carton of milk in this regard using magnetic stripe readers etc that integrate with the banking system. itll just take a significant amount of preplanning.. but to state its impossible shows a lack of knowledge in this arena. just saying.
If you implement credit to crypto, you're going to get defrauded left, right, and center... I think you're sorely missing something here if you honestly think you could pull that off and not lose all of your money.