If you book a ticket for a large city and there are 3-4 stations where trains are terminating/origanting and there are facility of retiring room then you can book retiring room in one of the stations of that city.
Like I have booked ticket for Kolkata (KOAA) station and when I searched for retiring room booking online there are KOAA, HWH, SDAH stations are present for retiring room to book.
So, in your case book ticket in any Hyderabad city station you can able to book retiring room in HYD, SC, KCG.