If the BD leg was originally booked on BD with a BD flight number before the flight was cancelled, they will give you the miles for it.

Bombay to Heathrow is about 4,000 miles. With the triple miles you would have c12,000 BD miles. 12,500 miles would get you a ONE-WAY economy flight from the US to Europe on 'cash and miles' (12,500 miles + £70 + tax). If you can credit a few Hilton stays to BD (1,000 miles per night, max 3k per stay) then you will soon hit 18,750 miles which is a one-way BUSINESS CLASS flight from North America to Europe.

I don't know the VS scheme at all, but its worth working out if you'll have enough miles for a one-way ticket from the UK to the US. If so, you may be able to swing it so you will have enough for a return flight, using BD miles one-way and VS the other way.

(PS. You SHOULD be able to double-dip on the 'BD now moved to VS' leg - BD will give you the triple miles because you were originally booked with them, whilst VS should also give you the mileage!)