MSI Script - Missing Terminator error

[mh-ch]

I'm using Crowdstrike to install/upgrade Cribl software on endpoints and, thanks to some of the discussions here, I've almost cobbled a PSFalcon script together to upgrade hosts, however I'm running into a "missing terminator" error that I hope someone can help me sort out.

So far I can put files, move them to the work folder, and stop the service, but the MSI installer (that does work using RTR) is giving me some trouble over PSFalcon, and it is likely my Powershell skills that are the problem.

Working RTR script:

Start-Process -wait -passthru $env:systemroot\system32\msiexec.exe -ArgumentList "/i C:\temp\cribl-4.x.x.msi MODE=mode-managed-edge HOSTNAME=<redacted> PORT=4200 FLEET=<redacted> AUTH=<redacted> TLS=true /qn /l*v C:\temp\cribl-update.txt"

How RTR script looks via CrowdStrike Audit Logs:

"runscript -Raw=```Start-Process -wait -passthru $env:systemroot\\system32\\msiexec.exe -ArgumentList \"/i C:\\temp\\cribl-4.x.x.msi MODE=mode-managed-edge HOSTNAME=<redacted> PORT=4200 FLEET=<redacted> AUTH=<redacted> TLS=true /qn /l*v C:\\temp\cribl-update.txt\"```"

Attempted PSFalcon script:

$Raw= 'powershell.exe -c "&{Start-Process -wait -passthru $env:systemroot\\system32\\msiexec.exe -ArgumentList \"/i C:\\temp\\cribl-4.x.x.msi MODE=mode-managed-edge HOSTNAME=<redacted> PORT=4200 FLEET=<redacted> AUTH=<redacted> TLS=true /qn /l*v C:\\temp\\cribl-update.txt\"}"'
$Raw = '-Raw=' + '```' + $Raw + '```'
Invoke-FalconRTR -Command runscript -Argument $Raw -HostId <redacted> -Timeout 300

The error I'm getting for the attempted PSFalcon script is:
stderr : The string is missing the terminator: ". + CategoryInfo : ParserError: (:) [], ParentContainsErrorRecordException + FullyQualifiedErrorId : TerminatorExpectedAtEndOfStringNotSpecified: ( :String) [], RemoteException

I have tried a lot of variation in the PSFalcon script, but the script posted above seems to be the closest and returns the most promising error output. I have a feeling it has something to do with single, double quotes in the ArgumentList section.

For comparison, this PSFalcon script is working great:

$Raw= 'powershell.exe -c "&{Stop-Service -Name "Cribl"}"'
$Raw = '-Raw=' + '```' + $Raw + '```'
Invoke-FalconRTR -Command runscript -Argument $Raw -HostId <redacted>

Any assistance is much appreciated. Thanks!

[mh-ch]

I found a workaround following advice from these sources:
https://www.reddit.com/r/crowdstrike/comments/mgg8o5/psfalcon_invokertr/
#33
PSFalcon rocks!