I received from @Eric_Inovelli a NZW37 dual outlet smart plug that I modified to act as a dual door garage opener. Upon opening it I was pleasantly surprised to see a well done clean pcb board with plenty of space to work on. You need a triangular screwdriver to open it up.
Here are pictures of the inside.
Top of upper pcb
Remove the two screws with a small Phillips screw driver and bend back top pcb.
Top of lower pcb
There are three Phillips screws to the left, right and bottom of the blue capacitor that you need to remove. Then you can remove the whole assembly from the casing so you can work on it.
Back of lower pcb
I unsoldered alll power lines (black, white and green) to make it easier to work on. I also removed the right hand side relay (only if you need control for two doors) to be able to cut the pcb trace undreneath, as the pcb is dual sided (no image for this). I also cut one pcb trace on the underside as I needed to isolate both relay contacts from power in.
Then I resoldered power lines for the outlets directly to the input power so they are simply pass-through, soldered a 4-wire cable to bring contacts out and mount it back.
Now I have a unit with two dry contacts output wired parallel to my garage door openers and a dual outlet.
If you do not feel comfortable doing it, there is a second option.
Get any relay with 120V ac coil and wire the coil of the relay to a standard plug. Then install the DTH as shown on www.inovelli.com, add your thing to the hub and go into settings for the channel you want. There is a setting to automatically turn off after a set number of seconds that you specify. So whenever to activate that output (with the associated relay) you will get a contact closure that opens after the set number of seconds.