Could you please describe in more detail how you did the syringe?
Doing it right seemed absolutely impossible, but was easy after I finally got it right. It was hard for me to watch too and I can't describe it in a way that seems helpful. Watching and doing are very different things for me and I need a diagram for anything and everything.
Here is my incredibly poor description which I hope will somehow help someone as desperate as I was:
Hand over chicken's head from the back, thumb & index finger very gently touching the corners where the beak connects to the head. That combination opens the beak and prevents the head from going back. Administer with thin syringe held in other hand. You're right; it has to be deep enough and at the correct angle.
I'm not sure what else I can add. My syringe was large--not the thin ones. I was giving 5cc once a day. I wrapped the bird in a towel, opened the beak by pulling the tip back (your way sounds better). The thing was to gently push the syringe to the side at the back of the throat and insert about 2 inches deep. Sounds like a lot and it was, but once in I pushed the plunger none of the meds escaped (not much that is) Some tries were better than others. It had to be done that was all there was to it.
I have since unwrapped the foot and it looked a lot better but there is still swelling there. I rewrapped the foot as I was told to do by the vet. I am waiting until Friday and will then begin working on it if it looks like it needs it. The poor bird really needs a break from me and me from her.