Confused
 

HI have an issue. I have a 2004 4x4 ranger 4.0 and It developed a loud rattle, and then on the way home started running really ruff, barely making it home. I pulled the engine, pull the front timing chain cover off, and sure enough, the plastic portion of the tensioner was gone and the chain had been loose and hitting the metal portion of the tensioner that remained. I then pulled the valve covers and turned the crank so the #1 piston was at the top, and the keyway on the crank was at top dead center, or 12:00. I then checked the slots on the cams to make sure they were parallel with the top of the heads. The right side is parallel but the left side looks to be at least a tooth off. How can this be when both cam timing chains, guides and tensioner are in tact? They both run off the jack shaft so how could one cam have jumped?
Also, the truck barely made it home. I
Can't see how, even with the loss of the tensioner, it would have caused the truck to run so poorly.
Lastly, from what I've read all 4.0 ranger 4x4s should have a balance shaft, but mine doesn't.
Need some feedback. I can't afford to replace all the timing components and reinstall just to find out the cams were correct, and by leveling the cam slots to the heads I screwed up the timing. I realize I've thrown a lot out there but any help would be greatly appreciated.