Remember that Medlock is an import, so the team would need to decide which designated import to drop if they brought him in. And we don't have his holder anymore, so he'd have to train another lefty holder.
And that leads to where Congi's problem probably lies - Fantuz being out means Bartel is holding for him. It takes a while to get comfortable with a new holder. If he's still having trouble in a few weeks with either Fantuz back or more experience with Bartel, then the team will need to look at other options. But I suspect they'll look to their PR/IR first.