Michael, that's the Siam Ruby! They are always like that coming with with some sales line to sell their stuff. Well, the world is big and they seems to follow Barnum's law very well.
I told you sometime back I got 12 pups from Bkk and my friend bought it from one source and all the plants turned up almost totally red. I was quite pissed cos I wanted some variation for comparison. Subsequently all the pups came up the same!
Then I was also thinking about another questionable plant from the description which you gave. This plant from Thailand is the
Kluay Saer Pran. Up till now no one can tell me its origin. This is
not the
Musa acuminata subsp sumatrana aka Zebrina aka Rojo. The markings on the leaves stay on till maturity and the underside is a glossy red. This is a slender plant. It is not common in cultivation. Saer Pran literally mean army Ranger with refernce to the camouflaged uniform they wear.