To my knowledge the verified pre-writer career Pat had was selling insurance. Niki even confirmed that in a podcast or video interview saying that Fat had had to renew his insurance broker license to be able to claim his residuals.
Regarding his claims to other “jobs”, my best guess is that he has helped at a weekend seminar or thinks that telling people stuff he read in Black Belt Magazine or similar, counts.
As for the competitive shooting, maybe he just means him and some people at a gun club have regular friendlies or he went to the same carnival sideshow several weeks running.
If he had competed even semi professionally there surely would be some trace of it somewhere.
There are people who have done a number of jobs before settling into a career path, but the things that Fat has claimed do require both serious training and or a military/security background, if you want to get a good reputation.
This sort of thing is not like saying you were a chef cause you spent a summer working as a line cook.
So either he is lying or maybe he managed to do a correspondence course and then helped out somewhere.
Either way, he often makes claims dependent on alternative facts.