I doubt if it has anything to do with rigging as if it had been ok since is was last done then why would it change?? If you look at the fwd and rear stops and they are not damaged then... The tail rotors being removed have no effect on rigging checks. The way that the tail rotor is designed it is not possible to fit it any other way. It does seem realy strange that it must have happened to both machines at the same time at different locations.
The PCL end sure looks like FOD to me or damage done during the last time it was off during maintenance but then that would have been picked up on the first pre flight?? If there is play in the spider or PCL's that would have been picked up on pre flight as well?? You say that the machines operate in dirty locations but no channce of FOD???
I would have a guess that the other damage could be due to someone inexperienced in changing the spherical bearings ( but this would have been seen on the first pre flight out of maintenance), FOD or gust lock damage ( if you use the blocks? ) is also a possibility.
On the spar cracking it it quite easy to see what appears to be cracks but it is just the resin coating cracking. The only time I have ever seen a real crack is after a tail rotor strike except for one which was fitted new from the factory, and if there is a suspected crack the tail rotor has to come off as you can't see much of the spar when it is bolted on. The book is quite definate on the check, 5cm push and pull flex from the resting position, I hate it when I see people pushing and pulling it from stop to stop.
Sorry to say but it does seem to be a bit of a witch hunt going on where you are whirls which is never a good thing. Maybe every one there should slow down a few knots and have a look at themselves before pointing fingers.