Indilinx was a research and development company with 45 employees and no fabricating facility when OCZ acquired the company last year. Indilinx still has no fabricating facility so some other company had to manufacture the so called Everest and Everest 2 controllers. You could simply say the manufacturer or source of the two controllers has been identified.
It is not any different from other branded components. For example, OCZ designs power supplies but does not manufacture them. In the past OCZ power supplies have been manufactured by 3Y, Channel Well, FSP, Impervio, Sirtec, and Topower. AMD does not manufacture memory. Their new line of memory is manufactured by Patriot. This type of information can usually be found in technical reviews. I guess for technical reasons that is not possible with ssd controllers.