the phone shop must arrange that with a bank and does not have the option of taking on risk
That's correct, any and all loans go through a bank. But please note that the bank won't advise if it's a bad loan, for example a ridiculously overpriced phone and/or phone plan. They just check if you can afford the monthly payment.
I heard SWIFT/IBAN transfers were permanent
These were card payments not transfers. Any payment done with a card, whether online or at a POS machine, can be reversed. And yes it was done for free in both cases.