206 T/R
VF - Old CE here, I thought it was customary (ie good practice) to fit T/R pitch links in pairs? And, of course, by the right P/N from the IPC, supplied by the OEM. And the other pointer that something is amiss is the Vibrex or 8500 imbalance issue. The technology NEVER lies; sometimes a little obscure, but you have to believe it and/or call or e-m the OEM. (Bell are one of the best at such matters, their database of 'sniggles' that don't respond to standard maintenance is legendary). And it's free too.
Well, thank goodness the aircraft was robust enough and did not fail in flight. Some lessons learned, I hope. Best - VFR
-VFR