I completely tore my left PCL a couple months ago.
Hamstrings are not relevant toward compensating for the structural loss in this case, the quadriceps are.
The PCL, in short, assists the ACL in countering translation of the lower leg.
Keep the quad strong and, especially as a sprinter, you shouldn’t have any problem at all.
Roger Craig, the great RB for the 49ers, played the majority of his career with a torn PCL (note the size of his quadriceps).
As for hamstring exercises, stay with those that extend the hip (back raises/hypers, reverse hypers, good mornings, RDLs, pull throught, and so on).
I’m not a fan of leg curls at all. If you wish to perform a knee flexion movement then perform the GHR, on a GHR NOT the floor version unless you have a makeshift pad that is large enough, and make sure the fulcrum is set farther away from the foot plate, closer to your hips, in order to ensure that the stress is directed more toward the muscle bellies of the hamstring and glutes versus the posterior structures of the knee joint.