I have a table in a module which has a row Action of type "Opens a webpage".
The value of that action's "URL of webpage to open" is:
https://www.google.com/maps/place/{{telemetryDataTable.data[i].latitude}}+{{telemetryDataTable.data[i].longitude}}
Now everything is fine when I use that action directly within the module. E.g., clicking that Action on a row will open this URL:
https://www.google.com/maps/place/-14.251672+-107.411498
But if I attempt to use that same button in an app using that module, with exactly the same data populating the table, the URL opens as:
https://www.google.com/maps/place/+
If I change the action to "Run a query" and access the underlying data from the table in the same manner, just within the query, I'm able to open the URL correctly in apps using the module, as such:
const URL = `https://www.google.com/maps/place/${telemetryDataTable.data[i].latitude}+${telemetryDataTable.data[i].longitude}`
utils.openUrl(URL, {newTab: true})
So if I have a workaround, why post in the forums, you ask?? Because it seems like I should be able to use the basic "Opens a webpage" with the [i] reference as easily within the module as outside of it, as happens in the "Run a query" approach! 
I'm not able to easily attach an exported test module as JSON since we're at our plan's module limit, but hopefully the above made sense enough to verify on your end.
Here are some screenshots associated with the code/values I pasted above:
DOESN'T work outside the module:
DOES work outside the module:
