The jumper remains in the batt/bind (“B/VCC”) during binding, then removed afterwards.
It’s just a wire (orientation inconsequential) used to temporarily short the pins and receive the particular signal from the transmitter to pair with the receiver.
I am not using the transmitter/receiver (Tx/Rx) furnished in the kit, but I see the included instructions state they come pre-bound. It also says if you do follow the binding procedure, you can plug the power into any other port. Also, to hold the “BIND KEY” while powering on. After binding, to ensure the binding plug is removed and insert the power plug back into that position minding proper orientation.
But Caleb has verified his procedure to work, which states to ensure you are providing power from the esc wire to Channel 3 with proper orientation of the wire (white signal wire towards label indicated by “S”).
If that does not work, ensure the batteries are furnishing enough power. Aside from that, it is possible you have a bad Rx.