Not really related, but could you dump the rom if it first?
(im not sure how easy this part would be without a working usb port, you would normally simply "adb pull /system" if it worked)
I doubt that there is an ota for it to begin with, they likely never made a patch for it since it isnt public.
(unless the glass team's policy differs from the standard android one) they generally do not make otas for combinations that they would not expect in the wild
Normally if this were a nexus device, the course of action would be to just use the factory image, but like you mentioned the usb port isnt able to be detected by a pc.
If you can root it without using the usb port, it might be possible to manually get CWM loaded on it and update with a manually made update zip. But without a usb port, if anything goes wrong then it would be very difficult to recover from that.