Richard I have not used Sciex Q-Trap. However reading this :https://sciex.com/Documents/brochures/Compendium_LowRes.pdf
It looks like you can do "Enhanced Product Ion (EPI)" on page 8
So yes, if you have the precursors, you can find the MS/MS for each of them and then develop your MRM. Problem is PRM as in Thermo (where you give a list of precursors and all fragments are collected) might not be available in Sciex. But you have to verify that option in the sciex software. Else, you have to collect MS/MS for each target individually.