This maybe a daft question but here goes anyway....
Mr M had to go for an Endoscopy, he was found to have mild Diverticulitis.
Would they have checked at his prostate at the same time?
What do you mean "checked" his prostate?
If it was so enlarged that it protruded into his rectum, then yes they may well have commented, but in my experience, the prostate is not checked during Colonoscopy.
A check on his prostate he would know about, normally its done by a Doc who pushes his 2 fingers up a mans back passage to feel for swelling etc.
(My H had it & told me how it was)