You don't have to worry about being a Vette devo on any board. (my opinion) I think that will not be a problem. At least it shouldn't be.
I just have one minor issue understanding this situation with your step-son's car. Was it running when he got it? If it was, then the broken chain tensioner and secondary chain were in running condition when he bought it. Anything that happened after that would have been spontaneous and not necessarily a sign of any prior owner's negligence, in my opinion. These engines should be healthy all the way to red line rpms, unless the engine is flat-out worn out. Then it is only bad luck if catastrophic valve train failure occurs.
That said, considering that the broken secondary chain or even the primary chain on that bank has occured on a running engine, is there also valve damage, as I would expect there to me? Maybe even piston damage. Which all leads to the obvious, perhaps a used engine would be the best way to fix this. I mean, head damage, including fractured camshafts, can be expected when you lose valve timing in a rotating engine.
Have you found anything in that head that looks like it is also toast? Because, if you've already ordered $500 in parts, that could be expected to rise. 16 valves and maybe 8 guides is potentially $1000 in head repair.
One other question would be, did you have any problem in obtaining the parts? Are these all available readily? I'm assuming dealer parts counter for all parts your son's engine needs.
BTW: I appreciate your honest reports of this engine tear-down operation. It sucks to be you guys right now, but we, the collective, are getting a minor enlightening education by your posting here.