With iOS 12 being out now, any chance of doors being exposed to Siri. This would allow you to toggle doors using 3D touch, and build custom siri shortcuts
I want this too
You can expose Garadget to siri by running Homebridge. I do this and am quite pleased with it. I get home, ask Siri to open the garage as I drive up to my house…
If you aren’t familiar with Homebridge, it allows one to integrate non-Homekit enabled gadgets to work directly with Homekit.
If you have a bit a tech acumen it’s really not that hard to enable. You can run it on a spare PC, Mac or Linux box. I just picked up a Raspberry Pi, installed noobs, and then Homebridge. Works like a champ! See this post, it’s what I used : HomeKit Integration with Homebridge-Garadget Plugin
HTH - best…Sean