I don't recall Dak every publicly complaining about the WRs (but I'm getting old so I may have missed it). But knowing that, I did Google for Dak comments about the receivers in Dallas, and I still could not find anything. Could you provide evidence for your yet-to-be-verified claim?
I do remember Beasley telling everyone to watch the tape (about getting open) and then when Dak "finally" threw a good pass that a Pop Warner WR could catch, Beasley flat out drops it. But did Dak throw Beasley under the bus against Atlanta even though he dropped the opening drive TD? Nope, Beasley was still targeted 7 times that game.
But please, if you can find where Dak threw ANY teammate under the bus, I will be more than happy to apologize and say "I was wrong" rather than stay ignorant and angry for no legitimate reason.