@elgerber I was going to suggest Venmo or plastiq as well. The fee with plastiq is slightly lower so if he can pay anything through there, I'd do that first. However, Venmo is a very good deal as well considering there is really no spend involved other than the fee which is worth it, imo, if meeting a MSR is too difficult otherwise.
I agree with
@SouthFayetteFan that these are more last resorts so unless you need to get the CP asap, I'd hold off to see if your ds can meet as much of the MSR organically as possible.
I believe there may be some info on DISchurners for using Venmo.
@Lain always suggests 'seasoning' an account first by making some smaller payments. Venmo can lock an account if they don't like something and the funds are tied up for awhile.