That was Wagner, which at the time was technically separate from Russia’s regular military. (Think of it as being akin to a private military company.) And they were lead by the head of Wagner. I think the equivalent in the Russian military would be Putin himself - so I’m not sure if we can expect the same sort of thing nowadays, as a military leader below Putin wouldn’t be expected to command the same level of loyalty over Putin’s army that the head of Wagner did over the Wagner troops.