I haven't tried what you are suggesting, so ymmv.
But I do have a Merten push-button with two buttons (or four as the two are spring-loaded and you can press both up and down on them), so I guess it will appear much the same to LMCE.
The problem with your scenario is that the device will only appear as one device for LMCE. So whenever one of the sensors trigger, LMCE will see an event from the same device. In other words you have no way of telling sensor 1 from sensor 2 etc...
At least, this is how I understand the problem.