Was this a fellow from the opposite wing of Islam?
All wings of islam are opposite.
Probably. The Shia, Sunnis, Wahhabis, and others don’t like each other. They may be united on the need for jihad against the West, but they will fight each other over control of the caliphate and what is the “right” interpretation of Islam.
Possible motivations:
* Shia, who resent the Sunni controlling Mecca and retrograde Saudi Wahabism being aggressively proselytized to their detriment
* Shia who want to get back at Sunni shrines for the destruction of a major Shia shrine in Iraq destroyed a few years ago
* Sunni fundamentalists, including ISIS, who see the Saudi development around the Kaaba the equivalent of Disney commercializing the Sistine Chapel and have advocated destruction of the Saudi royal family