I should amend my statement slightly, and agree you would have to see the play to know for sure. If A25 had been blocking on the line, then quickly turned around to catch the outlet pass, then contact by the linebacker could be a legal block.
If it was very obvious that A25 was NOT blocking and just waiting for the outlet pass, even if the defender was upfield, then it could be a foul. If it's questionable, I'd make it a legal block.