From your knowledge of wizardly adherence to habit, the way he never suggested getting items anywhere but the caravans, your knowledge of local markets, and the fact that everyone selling seems to recognize the Owle owl following you, you can be pretty sure that Wakalix bought all 836 of the items on his list from the same source(s) you’re currently considering.
(Regarding the other implications of your question, I neither confirm nor deny anything.)
From your knowledge of wizardly adherence to habit, the way he never suggested getting items anywhere but the caravans, your knowledge of local markets, and the fact that everyone selling seems to recognize the
Owleowl following you, you can be pretty sure that Wakalix bought all 836 of the items on his list from the same source(s) you’re currently considering.(Regarding the other implications of your question, I neither confirm nor deny anything.)