He could have done his job and met all the requirements, including attendance, and had his side business. A former boss of mine worked for a city office where he was in the morning that let him have a flexible schedule, owned a consulting business where he worked in the afternoon, and was a partner in a gym where he worked in the evenings. He did all that for 6 years and eventually reached his goal -- no boss, all passive income (ownership of the gym, tanning salon, real estate), paid-off house, etc.
I’d say that depends. I got sucked into a couple of different “opportunities” that turned out to be clown shows and I had to leave under six months both times. It was pretty hard on my CV, but what are you going to do?