I have in the past offloaded DG's because the paperwork is not correct! now I may be more qualified than the average pilot, as I used to consign DG's and have done about 6 acceptance courses and used to teach junior staff, but there is NO WAY KNOWN that I will lose MY licence, and my livelihood because some clerk stuffs up!!!!
generally, I have not had a problem, and as long as it looks kosher, then there will NOT be a problem on my little plane
very very rarely have I heard about crew offloading DG's because they can!
I got called once to see the captain of an A/C about some DG's that I had loaded. He had concerns, sop I raced down and saw him, with my IATA book, and the A/C loading manual. He explained his concern, I showed him where I got my info and said that if HE wanted it off, then that was fine with me!..... the DG's travelled.
GENERALLY, pilots WILL ask, if they have concerns over the cargo!!!!! before offloading it