It os hard to tell from the voltage coming off the driver, because they are constant current drivers, and they are trying to balance two phases of the motor.
Yeah, the M119 was just to see if it was configured for a y2. AFAIK, you can’t configure y2 without configuring the e1 driver, so that’s my quick check.
I would definitely try to work with it in series while talking to ultimaker. They seem to be pretty honest and they have pretty solid boards. I hope they would make it right.