Spies would inform the German government.

No.

Let's act as if Tippoo Tib were out of mind." We grumbled, but we yielded.

Hassan came again, shiny with sweat and voluble with offers of information and assistance.
"Where you gentlemen going ?" he kept asking.
"England," said Monty, and showed his own steamer ticket in proof of it.
That settled Hassan for the time but Georges Coutlass was not so easy.
He came swaggering upstairs and thumped on Monty's door with the air of a bearer of king's messages.
"What do you intend to do ?" he asked.

(We were all sitting on Monty's bed, and it was Yerkes who opened the door.) "Do you an injury," said Yerkes, "unless you take your foot away!" The Greek had placed it deftly to keep the door open pending his convenience.
"Let him have his say" advised Monty from the bed.
"Where are you going?
Hassan told me England.