Anybody in the castle should be able to hear Tama, the fact that he decided to show Sanji's reaction and not Chopper or Big Mom's is something worth mentioning.
Of course it's possible it won't lead to anything but it's not probable. I expect Sanji to protect Tama from Queen at the very least, Queen is just below the stage and he was listening to Tama after all.
The beast pirates are about to lose all of their gifters, someone has to (try to) do something.