I haven't had a set in my hand yet, but from what I understand these use "isky's 3 point oiling, so yes the roller should be feed by the valley and the pushrod

My thoughts on the cams is this...I could be wrong.

I think most(Isky,Luniti,Crower) are getting their pre Eagle/6.1 cam core from CMC, their only G3 offering is a .350 net lift cam ,.5775 with a 1.65 with a 1.65 rocker ratio
Comp has pre Eagle core that'll go higher. and I think(again I could be wrong) Comp is the only one with an off the self VVT cam core,I know Callies had a VVT Cam blank listed in the 2016 Catalog and I bought a few from someone who was at Arrington's auction.
Keep in mind one of the biggest limits to lift in the G3 is that long lifter bore. the G3 lifters are about 3.1 inches long from roller to edge of body,
to use a smaller base circle cam we need liters that are at least 3.20-3.25 in length
.660 is about the highest we can go with stock style lifter bodies , unless you mill down the yoke area and shorten the lifter bore...not an easy task.