Add DEF pump locations as well as DEF jug to fuel stations as a search criteria. DEF is also Generally known as ad blue. With modern diesels requiring DEF fluid or shutting down the vehicle the importance of it is high and yet unsearchable as a field like diesel. Some people prefer box/jugs others prefer nozzles/pumps.

There are positives and negatives to both. But, regardless not having DEF is a problem.