Kerdi / wet room compatible bathtub drain

[Chesterton]

I am turning my master bath into a "wet room". The shower area will be curbless, use a linear drain, and include Ditra-Heat. Adjacent to that space I will have a freestanding tub sitting on top of the tile. I need a way to perforate the Kerdi membrane for my drain while maintaining waterproofing for the entire space. In other words, I need is something like the Kerdi drain but for a 1.5" freestanding bathtub drain.

I have found the Oatey PVC Freestanding Tub Drain kit, which looks amazing but does not appear to be compatible with the Kerdi membrane. Same thing for MAAX F2 Freestanding Tub Drain kit. Part of me just wants to Frankenstein the Kerdi shower drain with Oatey tailpiece assembly.

There is also this product from Signature Hardware that appears to have a large enough flange that I could sandwich and waterproof it. https://www.signaturehardware.com/f...-kit-with-1-1half-2-in-pvc-outlet/446542.html

What suggestions do you have? I really appreciate your assistance!

Also, my question is similar to this one from 8 years ago (which did not receive any answers):

Draining freestanding tub inside shower

I've been all around the internet trying to solve this problem, the plumbers I've talked to in person haven't been much help. I'm doing a large walk-in shower with a freestanding tub. This is over a slab on grade so there is no access from below. I'm using Schluter Kerdi all through my...

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