Maybe they just have a larger company like QBC fill their orders.
During covid times maybe QBC (or?) has inadequate inventory.
I've had Amazon vendors that apparently ordered from other Amazon vendors for their inventory.
A few years back I had trouble buying a "good" cell battery.
I ordered from 2 different vendors hoping one might have a good one.
The cheaper one came promptly.
The more expensive one took another week, which is absurd, since we were both pretty much on I-5.
The both had the same lot#.