Y Axis driver failed, switch to E1?

I have been having issues for about 3 weeks with Y axis slippage and have just narrowed the problem down to the Y driver on the RAMBo.

Ideally I would just replace the board but I am on a serious time crunch having lost 3 weeks of print time.

Is there a way to reassign the Y output from the controller to the currently unused E1 driver? Presumably this is just an assigned value somewhere in the firmware but I am at a loss for how to create/modify a new firmware to achieve this…

Thanks in advance!