The Zeal of Omoz Arkosh custom loadout animation completely overrides the custom animations of the Pits of Omoz and the Dominator's Stance kinetic gems.

They should be compatible. The immortal does nothing but make Doom raise his left hand into the air. That animation can easily be combined with the animations of Pits of Omoz and Dominator's Stance, which make Doom hold his weapon differently in the loadout, which he wields with his right hand.

This is Doom's default loadout stance

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This is the custom stance of the Pits of Omoz kinetic gem

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This is the Dominator's Stance kinetic gem

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And this is the Zeal of Omoz Arkosh custom stance

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Here's what it looks like when combining the immortal with the Pits of Omoz, compared to what it is expected to look like

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Current

Expected


And here's the same with the Dominator's Stance

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Current

Expected