In fact you would have spoken to both centre's if you were high level as we transfer Midland inbounds to TC eventually. However as you mention Mode S that could only have been Terminal Control as LACC do not have access to Mode S data (that's another story!)
Your OPS department (I assume you have one that is) should have contact details for TC, PM me if you need any more help. If it was TC the watch that was working yesterday afternoon/evening will be on night shift or on day shifts on other watches today.