Dynamically changing URL's in an HTML File - Google Apps Scripts / Google Sheets

Question

I have written a script that creates a new "Report" every time it is ran. This is done by generating a new Google Spreadsheet, which then displays a filtered set of values based off inputs in the original spreadsheet it is tied to. Below is the code:

Report Script

The script is activated by a custom menu bar. An example of the menu bar is here below:

Menu Bar Code

Upon clicking into the custom menu bar, I would like the newly generated "report" spreadsheet to open. Since this script creates a new spreadsheet each time it is ran, the URL will be different each time, therefore, I am not sure how to incorporate the variable URL into an HTML file. Below are some lines of code I have used to open files upon using the custom menu bar:

HTML File Code

In the above image, "+ ssNewURL +" is where the known URL to the desired destination would go. I attempted to reference a variable I used earlier (ssNewURL) which gets the URL of the newly generated sheet, but it did not work. I have tried to get around the formatting issue of the HTML file which requires the URL to be a string; I've tried changing locations of double "" quotations, and single '' quotations. Whatever I have tried, the HTML file refuses to open.

I am extremely new to coding, I understand the logic behind it, however, I am very unfamiliar with every function/formatting of Google Scripts coding.

Any suggestions or workarounds for getting the HTML part of the code to open the dynamically changing URL would be greatly appreciated!