It’s philosophy of the Bills GM – he’s more willing than most to go after guys who played out west or on a smaller stage. The Dolphins prefer to grab guys from blue-blood schools and the SEC or B1G (see Waddle, Tua, Chop). Not sure if that has to do with where they played or their pedigree/expectations (higher rated guys with stronger athletic gifts are more likely to end up at bigger name schools)
The Bills meanwhile tend to take more shots on guys like Moss, Josh Allen, Dalton Kincaid, Khalil Shakir, Cole Bishop who may have flown under the radar initially, but excelled once they got a chance