I looked through all the other Eumenes images in the guide and couldn't find any with such extensive yellow and lack of black markings on the abdomen.

but color is generally a weak species character (MacLachlan, 1980; see genus INFO page). I don't have MacLachlan's key to the species (yet), so don't have a blooming idea beyond genus.
I just forwarded the same links to you & think you'll make good use of them; also shows how to differentiate Zethus, another petiolate eumenine wasp, from Eumenes. Those names certainly show early entomologists' preoccupation with Greek mythology.

I'm sure there was no preoccupation, these names were just a large pool of handy, memorable, euphonious 'hieroglyphs' to assign to the growing number of discovered insect species