[LorenPechtel]

It might not be a stolen card. Note that it simply says "someone else's card".

Maybe it's a corporate card, somebody in accounting decided to cause trouble. That goes along with why he's not mad at Robin--he realizes Robin was acting in good faith and the card owner is causing the trouble.

[jackatttack]

I don't understand why that matters. If Robin was acting in good faith, he would pay the owed amount. Then the contractor would pay Upwork and everyone would be back where they started—the contractor would be made whole, Upwork would no longer have a 'lien' on the contractor's account, and Robin would be back in good standing.

[LorenPechtel]

I'm thinking Robin isn't the primary, but an employee. Robin isn't going to pay out of his own pocket for what should be a corporate expense.