Compustar Pro T13, Existing Keyless Entry and Push Start, 2016 Subaru Legacy

Hello people, I am looking to install a Compustar Pro T13 remote start+ security system. That system has keyless entry functionality built into that remote. I want to install it on a 2016 Subaru Legacy 2.5i Limited that already has keyless entry/push button start and remote start. Installers tell me they can't do it and that the car needs to see the signal from the OEM remote in order for the car to be able to drive. I believe they are correct in that. They are saying that there is no way around it. I believe that a way around it is to hide one of the factory remotes in the car, remove the battery and only power it on using an auxiliary output or something when the system is unlocked using the T13 remote and the compustar system sees the T13 remote in range. Also locking the car at the end of the drive would cut off power to the OEM remote and not allow the car to be started if someone were to break the window and use the push button start to start the engine. (The OEM remote will need to be located somewhere far enough from the remote receiver module that's located on the deck lid behind the rear passenger seats, and far enough from the push button area so there will be no chance of the car picking the signal from the remote up even with out the battery in it).
What do you guys think?
Any better suggestions?
Thank you,
Peter M.

wait for compustar to launch it's "KEY LOCKER", and you will be able to due exactly what you want. your current method is dangerous and won't work

Thank you!