Upvote:1
The airport staff member at the head of the Nexus line did not allow us to use it, though it later occurred to me that perhaps we should have asked about a "diplomatic visa" rather than a "G visa."
The immigration officer attempted to fingerprint the G visa holder (and stamped the expired passport that bears the valid visa rather than stamping the new passport that is actually valid), so I didn't think he was likely to know anything and didn't ask him.
I thought about asking the preclearance supervisor, who was standing in front of a desk behind the passport inspection desks, but by that point it seemed more important to get to the gate promptly, so we did not.
The answer seems therefore still to be indeterminate, but if the Nexus lane really is available for this purpose, it will probably require asking for a supervisor to be allowed through.