How much do PE/HF headhunters make?

Having recently learned that headhunters in general get ~30% of a placed candidate’s first year’s salary (unknown if bonus is included), and the fact that a few HH dominate the industry to hunt for new blood for PE/HF every year, I became very curious to how much recruiters at these shops make.

The operations are so lean, and given PE or HF associate salaries and number of placements/candidates, I’d imagine the shops make $15-$20 million a year? That’s some serious dough if there’s a tiered revenue share after the partners get their pay. PE recruiter = more money than junior to mid level professional in PE?

Would really appreciate if anyone has insights to share on this. This industry is so opaque (and I’ve dealt with all of these HH firms) so I’m brimming with curiosity.