Remote execution of powershell script with autosys - to interact with IE _ComObject

I have a Powershell script designed to automate the testing of some URLs. The script invokes an Internet Explorer session as such:

$IEProcess = Start-Process -FilePAth 'C:\Program Files (x86)\Internet Explorer\iexplore.exe' -ArgumentList "-private $url" 

$Shell = New-Object -ComObject Shell.Application 

$IE = $Shell.Windows()

It then proceeds to use the $IE object to navigate to different URLs, perform various checks against the pages HTML document bodies and take screenshots of the resulting web pages. Ultimately, the IE session is ended and the screenshots are distributed via email as attatchments.

The script works perfectly when logged onto the virtual host-machine with a service account, that has the necessary permissions for single-sign-on to the various URLs. However, the requirement is for the script to run remotely as a scheduled task, on a daily basis. There should be no interaction by a user other than opening the resulting email.

I have had a job set up in AutoSys to execute the script remotely, once a day, with highest privileges; but the script fails to complete as expected. Specifically, the .Windows() method fails passing the following error message:

Exception calling "Windows" with "0" argument(s): "The server process could not
 be started because the configured identity is incorrect. Check the username an
d password. (Exception from HRESULT: 0x8000401A)"

I have to give the job of scheduling the task in autosys to someone else (for security reasons) but I trust that they have configured the job with the appropriate username/password for the necessary service account.

Some online sources suggest to me that the issue might lie with trying to use _ComObjects remotely, and that instances of Internet Explorer require an interactive user session with a UI - which isn't standard config for an autosys batch job.

I have had my autosys-guy add a flag to the job description which should make the user session "interactive", but the script still doesn't execute correctly.

I'm looking for some general insight on the topic and hopefully a solution to get the job running. If anyone cares to help me out I would greatly appreciate it! :)

I also have a more focussed question:

Even if I managed to get a handle on the IE session, should I expect the screenshots that the script takes to fail since the screen buffer for the VM has no monitor to render to? - The images are bitmap and refer to the IE shell objects "position", "width" and "height" for capture placement/dimensions; which presumably mean nothing without a screen resolution??

Thank you for taking the time to read my issue!