Old SCUP update hanging around

We had some users complaining about old Adobe Reader updates not installing from WSUS. The issue was inconvenient, but as soon as SCCM pushed more recent Adobe updates to the user, the issue went away. We decided to expire these old updates and remove them, however there was an issue. Whenever we attempted to publish the update as expired from SCUP, we got Verification of file signature failed for file: <Some cab file path here>. I had issues like this before and tried to remove it using PowerShell/.Net instead. I have had to do this before when we lost our SCUP database file. My go-to code for that is:

#This code largely from https://myitforum.com/how-to-expire-a-custom-update-in-wsus-using-powershell/
#Run this from WSUS for central site server
#Load .NET assembly
[reflection.assembly]::LoadWithPartialName("Microsoft.UpdateServices.Administration")
#Connect to WSUS server
$wsusrv = [Microsoft.UpdateServices.Administration.AdminProxy]::GetUpdateServer()
#Get all the non-microsoft updates 
$otherupdates = $wsusrv.GetUpdates() | select * | ? {$_.UpdateSource -ne "MicrosoftUpdate"}
#$wsusrv.GetUpdate($_.id)}} #Get more info on a specific update
$otherupdates | where-object { <#$_.id -eq "" -or #> $_.title -like "*adobe*"} | foreach-object {$wsusrv.ExpirePackage($_.id)}

This still did not work however, the script returned the exact same error as when the update is expired using SCUP. It turns out, the SCUP certificate that signed these cab files had expired about a month prior to this issue. In a last ditch effort, we were able to expire these updates by rolling the server time back to a time when the certificate was still valid. We were then able to re-publish the updates as expired from SCUP and the issue was resolved.