Here is a draft for discussion which uses a MRI-3.3D48 (to control the door) and 2 x MRI-24D48's (to signal the door status. One for PIN 5 and one for PIN 6).
The immediate concern that springs to mind is that the output side of the module's claims to operate down to 3V, and you will only just have that from the Pi, so it should work but without a spec sheet it can't be guaranteed. Same with the front end too.
If this was a problem, there are ways around it such as stepping the voltage with a Level Shifter.
Also, could you please check what current is being drawn when controlling the door (through PIN 1 & 10), I'm assuming it's nominal. Also what voltage is present on pins 5 & 6 when it's reporting status (either 0V or 24V?).
The Ras Pi I/O PIN should be pulled low (internal resistor) in the Door Controller, to keep the opto deactivated until of course the flow changes it's status.
