So for these cases you consider a high chance of the counterparty being dishonest, you use the alternative that can give you safeguards. If it makes more sense to use a credit card, you can still use it.
Since it is the customer who chooses the payment method (or just won't buy from the seller if they aren't happy with the options offered), what is the benefit for the customer?
The lack of fraud (by which you really just mean lack of charge back) is only a benefit for the seller, and not the buyer. You are just moving risk to the buyer, and it is just like the old days of the Web when some sellers would try to get you to use western union to pay.
I've not seen you describe this yet in the thread, which tells me there is no benefit or you haven't thought this through.
So for these cases you consider a high chance of the counterparty being dishonest, you use the alternative that can give you safeguards. If it makes more sense to use a credit card, you can still use it.