Only a problem for crew...
"All of which leaves NASA with zero options for resupplying the ISS with crew and supplies until the Russians work out what went wrong on Thursday."
They could send a remote-controlled Soyuz up with some supplies if they don't want to leave the ISS empty. AIUI, the problem is that the current return pod on the ISS has a "use before" date on it. Normally they'd send a Progress up for resupply, but no reason they can't use a Soyuz capsule (outside of cost and smaller cargo capacity) with no crew.
Obviously, they'd prefer to finish their investigation first. But if it came to risking an unmanned flight or abandoning the ISS, I think it's quite reasonable.