I think you are in good shape.
On the CP certificates: The fact that you have actually been able to get half the trip taken care of this far in advance is good news. And, yes, it's a shame that we have to call back continuously. But at five weeks out, for an international flight in the middle of February, the fact that half the seats (or more) in F show empty in a mock booking suggests that callbacks will pay off. This could be last minute; and, yes, there are last-minute full-fare customers who could swoop in. On the other hand, those same full-fare types are the ones who are most wont to cancel last minute, even after OLCI has begun, so don't talk yourself out of using the CP cert.
As for the tight connection, everyone is correct that it is dicey. But it could work, and that would be great. If it doesn't, you will be fine: You're CP, and this is a connection offered by US/LH, so if things are already slow-moving in CLT, they'll pre-protect you. Sure, you could end up not leaving until the 4:35 or whatever LH non-stop; or going at 1pm via MUC ... but those would be your only choices anyhow in "playing it safe." If you rebooked through PHL, you will have a lousier TATL set of take-off and arrival (read: "sleep") times, and now you'll have to worry about applying the CP certs on 2 flights.