You must get the "Kind" from the property.
# Gets the Kind of the member.
$memberKind = $member.Kind
You get the members from the class object.
$classModelType = Get-ProjectType $MyClassClass
loop through the members with
foreach($member in $classModelType .Members)
Verify that the $member is a property.
# if the member is a property
if($memberKind -eq 4)
verify that the type is "IEnumerable<T>"
if($member.Type.AsString -eq "IEnumerable<T>")
Checking for IEnumerable<T> may not be exactly what you need but Write-Host what the $member.Type.AsString is and you should see it.
Then check against that.
Hope this helps.