Anyone?
"The universe is a big place, perhaps the biggest."
Was that the mustachioed fella with the decidedly non-English, possibly European accent? I think one of the Brit soldiers pointed out to another that he was Czech.
It's reasonable to suspect he was from eastern europe and quite likley Czechoslovakia. He could have been an officer in the Czechoslovak army who escaped to England at the start of the war. Czech soldiers did fight on the British side in Italy and north africa, or he could have served in SOE working in the czech underground.
If he would have stayed on in the British army after the war it would have made sense for him to change his name to something British sounding like Rowntree particularly if he was commanding British troops.