I think the bill is still useful for separation. This bird (and the one in your first post) has a large, long bill with a sharp tip, unlike the bill of Tibetan but consistent with
columbinus. And as I mentioned in my earlier comment, the head pattern also fits for Greater - Tibetan has a longer, more obvious supercilium, more extensive white on the forehead and often paler lores.
Compare your bird against these Tibetan:
Macaulay Library ML611683310; © Gojko Kukobat; Muscat, Oman
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Macaulay Library ML612407473; © Jacques Erard; A'Sharqiyah South, Oman
macaulaylibrary.org
Macaulay Library ML610996929; © Mike Pearson; Abu Dhabi, United Arab Emirates
macaulaylibrary.org