Looks like the transformer is good.
Do not plug the transformer back into the board.
Power up the oven and check if there is 120VAC between the terminals P16-5 and P16-7 (where the red transformer wires go).
If there is no 120VAC then the control board has to be replaced but there is a chance the control panel is bad too (according to the error code you posted).
- The part number for the control board is AP3767567
In order to provide the right part number for the control panel I need the color of it.