Wrong, they never said that it will get into the index. They stated that the bitcoin cash that will be received from the bitcoins inside BLX will get distributed to BLX holders if I remember correctly. Probably in the form of BLX or some other way.
I still didn't get an answer what happened with Bitcoin Cash in BLX. it was clearly said we will get it in the index. No response here, and they do not respond on my e-mail requests. For me it looks like they had an exit strategy from the beginning. It's now Columbus Capital and not really Iconomi anymore.