PowerShell - Rename Contents of File Using names From CSV

I have the following script where the user is asked for the file server IP address, the IP is entered and the gpreport.xml file modified as needed.

$file_server = Read-Host "Enter the file server IP address"

$rootFolder = 'C:\TEMP\GPO\source\5'

Get-ChildItem -LiteralPath $rootFolder -Directory |
Where-Object { $_.Name -as [System.Guid] } |
ForEach-Object {
    $directory = $_.FullName

    (Get-Content "$directory\gpreport.xml") |
    ForEach-Object { $_ -replace "99.999.999.999", $file_server } |
    Set-Content "$directory\gpreport.xml"

    # ... etc
}

This works well, but I would like to automate it using a reference CVS file. I have 3 columns in my file - FQDN, Server Name and Server IP. I need PowerShell to identify current logged on users domain name ($env:userdnsdomain) and match the result to the CSV file below. Once matched, take the server IP column and insert it into gpreport.xml . This way the user insnt being asked for the Ip address of the $file_server and it's being done automatically.

Thank you.