Try the logic measure movement trick Artesia taught me.
Make a logic measure movement named whatever, and set the "entity to measure" as your func door. Then create a brush-based func_physbox you tile with NPC clip, name it something like doormeasure. Uncheck clients on your trigger multiple and make sure physics objects is checked.
You can set the measure reference to the LMM itself, and say place it at the bottom of the elevator shaft. Set the entity to move to the physbox and the measure reference to the LMM, movement scale 1, and measurement type position.
The physbox will make identical movements to the func door, and is capable of triggering the trigger multiple. You can tile it with something visible to make sure it's moving right, and then retile it with npc_clip after.
lol, for the record, i typed this at 8:07 and got distracted and forgot to hit reply until just now
