This function will run the repadmin command and format the results into a PSCustomObject.

examples.ps1

Get-ADGroup -Identity $GroupName | Get-RepAdmin | Where-Object { $_.Type -eq 'ABSENT' } | Select-Object -Property Type, Attribute, LastModTime, DistinguishedName | Sort-Object -Property LastModTime -Descending
Get-ADUser -Identity $env:USERNAME | Get-RepAdmin | Select-Object -Property Attribute, OrgTimeDate | Sort-Object -Property OrgTimeDate -Descending
Get-ADObject -Identity $GroupPolicyLinkDN | Get-RepAdmin -Verbose | Select-Object -Property Attribute, OrgTimeDate | Sort-Object -Property OrgTimeDate -Descending

Get-RepAdmin.ps1

#region Get-RepAdmin
function Get-RepAdmin {
    [CmdletBinding()]
    PARAM(
        [Parameter(Mandatory = $false, Position = 0, ValueFromPipeline = $true, ValueFromPipelineByPropertyName = $true)]
        [string]
        $Server = ([System.DirectoryServices.ActiveDirectory.Domain]::GetDomain((New-Object System.DirectoryServices.ActiveDirectory.DirectoryContext([System.DirectoryServices.ActiveDirectory.DirectoryContextType]"Domain")))).FindDomainController().Name
        ,
        [Parameter(Mandatory = $true, Position = 1, ValueFromPipeline = $true, ValueFromPipelineByPropertyName = $true)]
        [string]
        $distinguishedName
    )

    begin {
        Write-Verbose $MyInvocation.MyCommand
        Write-Verbose "Server: $($Server)"
        Write-Verbose "distinguishedName: $($distinguishedName)"
    }

    process {
        try {
            $objectClass = ([adsi]"LDAP://$($distinguishedName)").Class
            Write-Verbose "Class: $($objectClass)"
            switch ($true) {
                ($objectClass -eq 'group') {
                    Write-Verbose "Using group"
                    [regex]$line1pattern = '(?<Type>\w+)\s+(?<Attribute>\w+)\s+(?<LastModTime>\d{4}-\d{2}-\d{2}\s\d{2}:\d{2}:\d{2})\s+(?<OriginatingDSA>\S+)\s+(?<LocUSN>\w+)\s+(?<OrgUSN>\w+)\s+(?<Ver>\d+)'
                    [regex]$pattern = "$($line1pattern)\s+(?<DistinguishedName>.*)"
                    $return = repadmin /showobjmeta $DomainController $distinguishedName | Select-String -Pattern $line1pattern -Context 2
                    Write-Verbose "Return Count: $(($return | Measure-Object).Count)"
                    $return | ForEach-Object {
                        if ( $_ -match $pattern ) {
                            $Properties = [ordered]@{
                                Type              = $matches.Type
                                Attribute         = $matches.Attribute
                                LastModTime       = $matches.LastModTime
                                OriginatingDSA    = $matches.OriginatingDSA
                                LocUSN            = $matches.LocUSN
                                OrgUSN            = $matches.OrgUSN
                                Ver               = $matches.Ver
                                DistinguishedName = $matches.DistinguishedName
                            }
                            [PSCustomObject]$Properties
                        }
                    }
                }
                default {
                    Write-Verbose "Using default"
                    [regex]$pattern = "(?<LocUSN>\d{1,10})\s{0,6}(?<OriginatingDSA>.{0,36})\s{0,10}(?<OrgUSN>\d{1,10})\s{0,1}(?<OrgTimeDate>\d{4}-\d{2}-\d{2}\s\d{2}:\d{2}:\d{2})\s{0,6}(?<Ver>\d{1,6})\s{1}(?<Attribute>\w+)"
                    $return = repadmin /showobjmeta $DomainController $distinguishedName | Select-String -Pattern $pattern
                    Write-Verbose "Return Count: $(($return | Measure-Object).Count)"
                    $return | ForEach-Object {
                        if ( $_ -match $pattern ) {
                            $Properties = [ordered]@{
                                LocUSN         = $matches.LocUSN.Trim()
                                OriginatingDSA = $matches.OriginatingDSA.Trim()
                                OrgUSN         = $matches.OrgUSN.Trim()
                                OrgTimeDate    = $matches.OrgTimeDate.Trim()
                                Ver            = $matches.Ver.Trim()
                                Attribute      = $matches.Attribute.Trim()
                            }
                            [PSCustomObject]$Properties
                        }
                    }
                }
            }
        }
        catch {
            Throw $_
        }
    }

    end {
    }
}
#endregion Get-RepAdmin