Shadow 2 owner with 3XL glove size hands. I have the same issue. Love my CZ, but my hands are just too darn big to get a proper trigger finger poistion.
My stop-gap solution is the thickest Armanov grips + double grip sleeves. I cut the top of grip sleeves to allow room for the mag release.

It works... but it really doesn't look good and does not do the gun justice.
I have emailed both LOK and Armanov. LOK said no one else has asked grips with backstraps, while Armanov told me the backstraps weren't allowed in some competition divisions. Either way, they are both saying they dont think there is enough of a market for them to produce it.
After exhausting all other options I decided to custom order Rink grips from Germany (Pardini imports them into the US). I chose the largest size and thickness possible. They are for a CZ75 so I might have to do a few mods to get a perfect fit. Grips should arrive next month and I'll do a review.