Modifying an Environment Variable remotely with Powershell

Question

I've got an environment variable that is used by multiple applications. For one of those applications, we are starting to use a batch script to set that variable on application startup. I'm trying to get write a powershell script that will only strip out certain parts, almost like the PATH scripts that I've seen elsewhere. Let's say I've got an environment variable named LICENSE_FILE that contains "LicSrv01;LicSrv02;LicSrv03,LicSrv04".

I want to strip out LicSrv01 & LicSrv02, leaving the rest if they exist in that variable. Here is the script that I've tried.

$license = invoke-command -computername $client -Scriptblock {[System.Environment]::GetEnvironmentVariable('LICENSE_FILE','Machine')}

if ($license -ne $NULL) {
    $license = ($license.Split(';') | Where-Object { $_ -ne 'LicSrv01' }) -join ';'
    $license = ($license.Split(';') | Where-Object { $_ -ne 'LicSrv02' }) -join ';'

    invoke-command -computername $client -ScriptBlock { [Environment]::SetEnvironmentVariable('MGLS_LICENSE_FILE',$license,[System.EnvironmentVariableTarget]::Machine) }
}

This works on a local PC, but when I run this on a remote PC the script wipes out the entire environment variable.