This has been mentioned 100's of times. If you not going to prep the model proper before trying to import it, you will never know what is wrong with it.
Open it, look at the number of objects in it, (this case 3 copies of the same model), should have been an instant clue.
Most formats are 65000 face per object or thing don't get rendered.
Been this way since classic fpsc. No more then 63 bones with no more then 3 bones pulling on any vertices.
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