As @JDRoberts mentioned, if you have Android device that you could dedicate to the cause and Grid-Connect has an Android app, then you very likely could put together a Rube Goldberg integration with Tasker.
You would have to use something like AutoInput with Tasker to automate the various presses in the app. The process is far from the recommended solution, but if it’s the only option you have, then it’s worth a shot.
The SharpTools Tasker plugins (for Android) can act like the glue between your phone and SmartThings. The SharpTools Tasker plugins can be used to send commands / updates from your phone to SmartThings… as well send messages from SmartThings to your phone.
As JD mentioned, we also offer SharpTools.io Dashboards and Rule Engine which are both web based. But what you would need for the Grid-Connect device is to first figure out the local integration with Tasker and AutoInput… then use the SharpTools Tasker plugins as the glue between Tasker and SmartThings. 