If you put infernalis in tetrataenia, you have no tetrataenia anymore.
So personally I want to keep my animals as pure as possible.

By the way... Two thousand dollar for a pair T. s. tetrataenia´s is a lot of money!!
I bought my three specimen for € 75,--, € 110,-- and € 125,--. This are the normal prices for juveniles in Holland (and the rest of Europe?)
Do not know the prices for adult specimen, but more than the double of what I mentioned for juveniles it will not be.