I think it should.
That being said, I think the reason for it being different, is that ''Sentient Singularity'' is a part of the ''Gleam of Sentience'' meta-gizmo (if that's even a real term 😛 ).
The Gleam of Sentience works as a vendor.
Ohh. As I wrote that out, something occured to me. What if there's some sort of conflict between ''different'' vendors with the same ware? Like, could you do 6 purchases from Sentient Singularity *And* 6 from gleam of sentience, forcing you to carry all 4 items around?