Green with a caveat: TT for DHN-ROU section is overly aggressive. The train should leave HTE at 09.40 (so about an hour off your TT). And from there on, it can follow HTE-LTT TT. In other words, your imaginary train is basically HTE-LTT SF, extended to DHN. :)
I have previously considered an imaginary SF running between HWH and LTT via ASN-DHN-HTE-ROU, potentially in 34 hours, even sharing time slot with another possible SF, this one going to Pune via Panvel-Karjat, or may be MAO/Mangalore.