I would say if he cried for 2 hrs that PU/PD is probably not the right method for him. PU/PD is not a great tool for Spirited babies and it may be that it's not a good match for your guy. For what it's worth, I only used Shhh-Pat with my boys and they are the most chill babies, they just found Shh-Pat more soothing.
In regards to settling, most babies take about 20-30 mins to really settle into their nap. They may grouse and wiggle about and they may even do a half-hearted mantra cry (doesn't change in volume or tone and will start and stop). However if your baby starts to genuinely cry his "I need you1", please do go to him.