Both, actually. With 0 volts present, you should not get any deadkey wattage, as there shouldn't be voltage present on the TP7/TP8/TP9 rail. TR50/TR51 is designed to drop and regulate the voltage going to the Source pins on your driver and final (center leg), usually to the tune of 4-7V, depending on where your deadkey VR control is set.
The thing to do is take both TR50 and TR51 out of circuit, and then check for voltage at TP7/TP8/TP9, there shouldn't be any voltage present. If there is, there's a bad trace, or a bad solder joint somewhere that's dropping voltage to that rail. Check for any burnt traces or bad solder joints, as these radios are notorious for bad solder joints and bad traces. If everything looks good, reinstall new transistors at TR50 and TR51, and double check voltage at TP7/TP8/TP9, you should have 4-7V roughly on that rail. If it checks 12.5V+, there's a fault in the regulator circuit.
~Cheers~