Hi Matthew
To add to Atom’s post, the VM and BWM were issued as a pair, so both medals should be impressed with the rank/number signified by the cross with four dots. The 1914-15 Star should be impressed with his rank/number on the date he ‘entered theatre’. As you have the medal can you say what is on the 1914-15 Star?
Entering theatre actually means the date he left the UK. This was usually only one day difference, if being sent to France. But if they were going to other theatres the trip would be longer and they would have received the overseas allowance for the trip.
If by ‘meritorious’’ you mean the Meritorious Service Medal, I have a medal roll and I cannot find him under RAMC. Can you say which monarch is on the obverse, and what is impressed on the MSM? These were usually issued to long-term service men, often many years after they were discharged. If he served into the 1920s his papers would not have been released to the TNA, and may still be with the MOD. Do you know when he was discharged from the army?
Ken