being a former CDL driver myself, if the trailers are full to a certain weight or volume of hazmat, then the CDL trailer driver MUST have the hazmat endorsement. UPS, makes sure of that, when one get's hired, i know, i had applied there, long before i had retired.
the "city" drivers that drive the "brownies" do not necessarily need to have the hazmat endorsement, as the weight of the brownie trucks are well under CDL rules, and most times there isn't all that much hazmat to be delivered on the trucks.
it is highly possible that this covid crap is still setting back all employers, as such that many employee's may not be back to work.