Lol That screen shot proves nothing at all.
If he is on a jaymod server the hs to kill ratio looks fine, considering the noob meds running around with adrenalin and fast recharge effectively having about 400 hp's, not to mention oasis is a large map, where you may be affected by distance fall off.
And your more likely to have a lower accuracy with more head shots obviously...?
Ive played on a jaymod server before and had 22 kills and about 80 head shots with a 45 acc and i can assure you that i do not cheat nor am I'm i overly good.