No, SDAH DURONTO still getting some Passengers from SDAH if it is shifted to SHM I don't think it's Patronage would be increased rather it will decrease more which is decreasing now. SDAH Duronto should be converted to "SUPERFAST" if it's patronage is to be increased and change in TT also required.
Regarding PNBE Duronto it can be terminated to HWH instead of SHM but as HWH is already congested so I think SHM is fit for it.