Identificaciones de khcarter

Found in high quality sand prairie remnant (sand blow out). I thought at first this was auricomus but Laura Anchor believes its likely fraternus? There were at least 6 of them all over the green milkweeds (Asclepias viridiflora).

We recently found several (unlabeled) B. affinis specimens in an extensive collection donated to the university by a (late) former employee. This is the only one with any metadata beyond 'New York'. Collector listed as E. Freedman (who is not the owner of the collection). Location listed as 'Syracuse'.
Sorry for the poor digiscoping, bumblebees tend to be too big even when at lowest magnification...