The engineer 'mentioned' the collective friction. That suggests to me that it hasn't been checked. My experience is with the 205A-1, we had a case of collective bounce with an underslung load, which resulted in a heavy landing. IIRC there was very little in the MM about the collective friction adjuster apart from the static friction value. I add the following in case the MM is still deficient, please forgive me if the following is patronising it is not intended to be.
It is easy to check, remove the co-pilot's seat and the floor panel, disconnect the collective bellcrank and place a spring balance in the bellcrank and pull the collective up. Until then we had not ever checked this but we did every 100 hrs after that.