vtraudt

Previous owner found plastic piece in oil pan. Audi shop told me he needs new cam chain tensioner/adjuster.
Car runs like crap.
Tons of misfires on bank 1 (passenger) cyl 1-3.
VAGcom timing blocks 90-93 show 34 deg bank 1, -3 deg bank 2; cam ctrl off phase (block 93) zero and zero.

crank on TDC, cam lock bar installed: good timing

valve covers removed: no visible damage to chain tensioner guides (obviously only upper part); chain seems tensioned.

a) what can cause the intake angle so different between both banks and misfires on bank 1?
b) if chain tensioner/cam timing adjuster is suspect: how to determine if it is good or bad?
c) any suggestion for further diagnostic? Or rip out one or both cam adjusters/cams/seals (expansive)