Break it down. The dog had a bird in his mouth and spit it out. That is a violation of "Hold". Start there.
I suggest you sit him, put a bumper in his mouth, and then walk 20 yards away. Whistle him to you, and as he approaches toss another bumper (not at his face, but off to the side). If he spits it the first bumper, reinforce "hold" of the first bumper. Don't worry if he watches the diversion bumper or even veers towards it, as long as he doesn't spit out the first bumper. Give lots of praise when he does it correctly. Also let him pick up the diversion bumper only when he does it correctly. It won't take long for him to realize he only gets the second bumper when correctly delivers the first bumper.