Graphics bug in battles with certain Eastern and Islamic units

[quarterturnback]

In battles, I get a weird graphics bug with certain units, pretty much only certain Eastern and Islamic ones. When the camera is level to the ground looking at the unit close up, or when the camera is zoomed out and panning over the battlefield, the "unit captains" of these units have strange skinny wedges or poles projecting out of them into the sky. I'm attaching a photo to show what I mean.

I'm playing SS 6.4 with the 1.27 bugfix on a Mac.

Units I've found this problem with so far are:
-Kwarezmian Mercenaries
-Lamtuna Spearmen
-Turhagut
-Armored Horse Achers
-Dismounted Khagan Druzhina
-Khagan Bodyguards
-Dismounted Khagan Druzhina
-Heavy Spearmen
-Arab infantry
-[Bodyguard cavalry for Muslim factions]
-Fari Cavalry
-Heavy Archers
-Arab Cavalry
-Christian Guard Cavalry
-Dismounted Sipahi Lancers
-Janissary Archers
-Janissary Arquebusiers
-Janissary Musketeers
-Janissary Heavy Infantry
-Qapukulu
-Halberd Militia

[badcore]

Exactly the same issue for me! Same version, SS6.4 with bugfix compilation 1.27, on Mac OS 10.14.6

Islamic captain meshes seem to be broken. I suspect this is Mac-specific issue, otherwise it would be hard not to notice for the rest of the audience. So we, Mac users, are alone

I found the culprit file: data/unit_models/_generals_and_captains/islamic_captain/eastern_captain_early_flag_lod0.mesh (relative to mod's root directory)
I just replaced this file with a file for some different unit (of course I kept a backup), mesh for some european knight in my case, and this pole projecting to the sky gone away. The captain now looks like an awful frankenstein because its mapping to the texture is wrong. So this is kind of a workaround.

I would be happy to edit the mesh file myself and publish the result, but I have no idea what the format it is, which 3D software can read it. Dear @Developers, any hints from you will be highly appreciated!