Ohtar in Heroes 5

All Scouts, Assassins and Stalkers in hero's army gain +1 to their Attack and Defence for every two levels of the hero, starting on first level.

Everybody knows Ohtar as a bad guy. However, nobody knows what misdeeds he has made exactly, possibly because he never leaves witnesses alive. He says that it is just a slander, but why do Scouts and Assassins follow him everywhere then?