I was a ARRL ve I think my credentials have expired due to non participation. I also have W5YI VE credetials as well, both sice 1994. I was the contact VE for a local conbined 2 club group for 5 years. I was unaware of any fraud, but had 3 complaints from sore losers.
Both VEC's backed me, and the other 2 VE's who were responsible. One of the sore losers confronted W5YI at Dayton Hamvention. I burned out from the 8x a year hassle. I quit.

The old farts who bitched about the demise of spark gap also did not consider a VE examined ham to be a real ham. VE's have been around forever. I got my novice from a VE. Back then any General class or higher over 21 years old could give the novice exam. The written exam was mailed to them. They administered the receiving, and sending code test. They broke the seal on the exam envelope like a big deal, and handed you the exam, and answer sheet. When you were finished, they placed it in the mailing envelope. Then you had to wait 6-8 weeks for a license, or a failure letter in the mail.

I would be curious if there is any data of FCC exams by federal employees that were fraud stained? There was a time when at Federal buildings, and post offices, the exams were conducted by post office employees. I am not sure if they graded them.

I just remembered a very caustic ham who would tie up local vhf repeaters a while back. He seemed to go out of his way of being anti social, and anti establishment. He bragged about cheating on his codeless tech exam. He was one day ordered by the FCC to show up and retest at any non-W5YI VEC. I guess he complied. He dissappeared as well. I guess one should watch what they say on a repeater. I really do not think he cheated. He was just trying to piss people off (and succeeded).

Other than that I am not aware of any fraud in a VE exam that I was part of. I probably participated in several hundred exam sessions including several years at Dayton Hamvention. (it was a free ticket).