I've done this, though I haven't done it lately.
His ganks are surprisingly not where he fails this test, but the clear times an counter-jungling. That and his ammo replenishment is pretty gimped right now, which is another area he falls in normal gameplay anyways. Basically other junglers get better results. He starts needing farm and lacking on total growth via itemization.
Here's a couple ways to gank with turrets:
Over-extended target top, drop your turrets on their escape path. They will start backing off into turrets as muscle reflex. Effective top lane for blue team, bot lane for red team (the tri-bush as your entry makes getting to the turret a not-safe thing.) Equally when your ally is overpushed, you can hinder waves to make the enemy sitting ducks in some scenarios. (not for long)
Lure and Ambush, trick them out of lane into waiting turrets, this requires team coordination. Most effective mid, but risky. More effective if they're using Greenfather's as they'll try to bump up a nuke by dodging into the bush just prior.
Wall-drop turrets. This works all over the map, but you need practice for it to work well. This is all about placement and being smart/clever. Get into the enemy Raptor circle, drop turrets on the wall to make their placement on the opposite side. From your placement, rockets can get them under their tower. Ward behind you since you're likely using 3 ammo stacks for best effect. This works at Dragon, but is tricky at Baron pit. This works on that weird loop near gromp, dropping into the river or behind/under enemy tower. Gromp wall itself allows you to stall/stop minion waves from reaching bot tower, this can be useful for other reasons. Just remember that the second your turrets are visible as active, your enemy knows you're near, hence the ambush from over the wall.
None of these are standard ganking patterns, they rely on clever usage of placement to create a situation that negatively impacts your opponent. You need coordination definitely. Be smart about how and where you do these.
Alternatively... take Heim top, take herald after a good shove to get your enemy out of lane and hyper-push... or something.