Try the best you can to get that bracket out. Just don't break anything else in the process.
Worst case scenario, if there's just no way at all to get that bracket out (say the screw head is stripped and you're not comfortable or don't have the tools to safely drill it out), you can CAREFULLY break the tab off the new plate.
It's a... "not quite completely professional" solution, but if it's your phone, and you're not regularly prying at that corner for some reason, the other brackets should hold the face plate on more than sufficiently.
Thank you Bradley. I've had tons of grief with this screw in the past. I've just had to turn the driver at an angle and curse and yell and retry it 5 times before it worked. This is a MUCH better approach! I had no idea that cable safely had that much give. You have my gratitude.