Rough idle / bad rocker?

[OutwardBound]

Hey everyone, new here but am a Ranger owner twice over. Current one is a 2004 XLT, 4.0 SOHC, 4x4, 5 speed, extended cab with ~165k on the body & 90K on the motor (as was told to me by the PO) I've had it for 2 years now. Truck has been great up till last week when I started to notice a miss at idle. Then just this past Wednesday it tripped the CE light. Codes are P0305 and P0316. Checked compression on cylinders 4/5/6 this morning and got 4@180psi / 5@135psi / 6@185psi COLD. Plugs looked ok. Popped the valve cover off and found the intake rocker/roller on 5 toasted. Also the Cam overall not looking great, although its not seriously pitted, so it feels. Springs look ok. Do rollers sometimes just cease to "roll"? Could the wear already on the cam have caused the rocker to go? How to check its getting oil? I was about to ask if I "could crank it while my buddy watched..?" but.. uh.. let me rephrase that - Could I turn the motor over with the cover off and then see if its getting oil that way? The only thing I've done differently in the last few weeks was tow a mototcycle (400lb sport bike) about 3 hours home with a uhaul trailer, but I had no issues. Any thoughts/suggestions are appreciated, I guess at this point I'll source a rocker/rockers and maybe a Cam? and go from there or what else should I be checking/looking for? Thanks guys.