By Joseph Salvador He was taken back to the locker room but later cleared to return to the game. The NFL player’s association is launching an investigation into the Dolphins’ handling of Tua Tagovailoa’s concussion check Sunday against the Bills, per NFL Network’s Tom Pelissero. Tagovailoa left in the second quarter of the AFC East contest after taking a hard shot from Buffalo linebacker Matt Milano while attempting a pass. As he fell to the ground, Tagovailoa’s head hit the ground. Milano was flagged for roughing the passer on the play. The Miami signal-caller attempted to quickly stand back …