Well R'lyeh had just lost a large force within Jotun's lands. In that battle he lost a lot of commanders. It is possible that many were equipped thugs and mages and that is where most of his items went.
I can confirm that no items were sent to his other ally at the time - Mictlan
Shin would surely be a more likely provider of Rune Smashers as he can build them from his main mage???