You joined a onyxia pug, by the gear you wore you coudn’t be classified as a protection warrior, everyone in the raid tought you were a dps, but terribly specced. nor did you actually preform the warrior tank role on onyxia.
you did pull agro of the tank as a spec on onyxia.
for your information, the tank i played together with in that raid wasn’t my friend and i have never seen him since.
the onyxia went MS>OS and 2 helms dropped & there were 2 tanks, so logically in that situation it was decided to just give them to both tanks.