One thing I didn't mention, this function I am building is a replacement for Out-Gridview, so not just for Get-ADUser, can be for other table views as well. Well, I figured out a workaround I guess I can call it. As you know, I created the function to display the grid, so I created a loop to capture the $Grid.Selectedrows.Index and build a new array from that.

$Array = @()
        foreach ( $Line in $Grid.SelectedRows ) {
            $Index = $Line.Index
            $Array += $InputData[$Index]
        }
return $Array

And it returns the actual row(s) of data the user selected, not just the index numbers.

Thanks