You overrate leech, leech is not that good against a single mob, Kowbat hits you for a good 1-2k dmg on 1p and 4-5k on 8p, also Kobats HP is not nearly good enough for you to regain that hp back, even from 1 hit. Never mind after Kowbat is Turrets then Xab.
Kowbat is indeed glitched, also just to not you can't get hit by the fire attack when you are on the pillar, just his normal atk, and drill. Kow's drill atk is kinda glitched and it can happen any time even 2x in row, and there is little to no animation for his drill attack, that can make you tell when he will use it.
Kowbat takes Ross about 10 seconds to push easy game, also being a ram and the fact Ross is transed at that it takes around 2 mins to kill Kow.
Sooo 2 mins - 10 seconds = 1 min 50 seconds, chance of lose is basically 1/5, thus lets say 4 are successful and the 5th is not. It takes Ross 3 minutes to reach Kowbat.
4 games pushing kow x 1min 50 seconds saved = 7.3 mins saved, however on the 5th game Ross loses out on a 3 min game, thus making it 4.3 mins saved.
Oh also, Ross combos / uppers xab and gets hit down by the turret until his hp is red and then he upper spams, if he does however lose HP at Kowbat, that means Ross will get red even sooner at Xab slowing down the Xab wave also.
Hams method is better than this, heck even just upper spamming him where he spawns is faster and safer than this method.