I don't think anyone from coastal karnataka will travel in 2 VBs to reach Mumbai, that too in day time.
No halts of MAQ MAO VB at convenient places (Kundapura, Bhatkal/ Murudeshwar, Kumta, Ankola etc).
Can be a tourist train if it starts in the morning at MAQ and reaches Mumbai by night. As a direct train, not as 2 parts.