Is it possible to integrate a turbo timer in the tune? Seems like you would need an available digital input to the ECU.

A turbo timer is not feasible with the tune. The software needs to change to incorporate this feature. It would need to be a standalone feature. It would just be cheaper and easier to leave the engine running for about 30 seconds at idle before turning it off, this is only needed after running at heavy loads and should not be an issue in normal driving conditions.