Both the drives have C13044 on the bottom of them. The T drive works, but the non T doesn't. I'd be tempted to try swapping the boards to see if the problem moves with it, but the working one (T) is perfect so I'm not touching it.
That's inverted from my WD-387 and WD-387T pair that are marked the same way ('C13044' label on the bottom and the same sequence returned from 1C0Bh). I've sampled enough drives now to know your drive PCBs are marked as '1988' - in fact, the oldest I have found with mine that still works, and every '1987' PCB drive I test has failed!
In fact, the versioning isn't even a sequence of "a larger number means later", and the 'MLC' value on the label doesn't resolve very well. I've compiled this sequence for the '32 02 00 xx' series. First is the entire table of returned 1C0Bh values, then converted to what would be in the 'microcode' field, the 'MLC' of the white label, drive model, and small label(s) on the PCB, with the 'Control Program' year last:
E9-06-00-00-19-00-02-32-00-00-00-00 = 32 02 00 19, MLC 'C13035', WD-387, 'C13044', '1988'
E9-06-00-00-19-00-02-32-00-00-00-00 = 32 02 00 19, MLC 'C13044', WD-387T, 'C13044', '1988'
E9-06-00-00-20-00-02-32-00-00-00-00 = 32 02 00 20, MLC 'C13101', WDL-330R, 'C13130-A', '1989'
E9-06-00-00-22-00-02-32-00-00-00-00 = 32 02 00 22, MLC '341669', WDL-330R, 'C27353-A', '1989'
E9-06-00-00-22-00-02-32-00-00-00-00 = 32 02 00 22, MLC '341669', WDL-330R, 'C27386-C', '1989'
E9-06-00-00-24-00-02-32-00-00-00-00 = 32 02 00 24, MLC 'C81194', WDL-330R, 'C81194-A', '1989'
E9-06-00-00-50-00-02-32-00-00-00-00 = 32 02 00 50, MLC 'C27850', WD-387, 'C64391-D', '1989'
E9-06-00-00-50-00-02-32-00-00-00-00 = 32 02 00 50, MLC 'C27850', WD-3158, 'C64391-D', '1989'
There is a later sequence that even starts using one byte of a 'reserved' field:
E9-06-00-00-00-06-01-30-00-36-00-00 = 30 01 06 00, MLC 'C81004', WD-3160S, 'C81004', '1990'
E9-06-00-00-02-06-01-30-00-36-00-00 = 30 01 06 02, MLC 'C81555', WD-380S, 'C72778'/'285010E', '1989'