I’ve seen many aftermarket alarms cutting and splicing into the DME harness where they interrupt power to the DME. The Porsche implementation is the same for 3.2 and early 964/993. The later 95 DME is actually a real data exchange between the immobilizer device and the DME. That’s when the DMEs became smart.

It is unfortunate that the alarm hampered the running of my car. It certainly wasn't the crummy install of it. The installer took great care in how the wires were run, tucked up neatly into crevices connected with raychem as opposed to the the diy crimps. Fortunately the alarm is still operational with all the alarm features and such. All I lost was the ability to disengage the startup when the alarm is on. Which is a good thing because now I can start it myself.
Tom