I've got a lot of ECY in the fridge I haven't brewed with or slanted yet. I'll have to look when I get home, but I know there are at least 6 or 7 vials. Belgian white, Trappist, kolsch, single strain saison, bugfarm and flanders red are there for sure. I don't know if there are any micro-biologists in the group capable of examining the bugfarm and flanders red to see what the proportions are to try to replicate those. I do know that splitting them into multiple starters does not lead to the same results as using the whole bottle as directed.
I can slant any of the single strain yeasts if people are interested. The kolsch makes the best spotted cow clone I've had, much better that using wyeast kolsch.
Its for sure possible to determine the composition of the mixed culture but i dont think its worth it. To get it really accurate would be expensive and i can tell you already that ratio of different bugs will be different than in original package because grow rate is different and survival on slants can also play a role but it is impossible to say how different beer you get using slants, i would just go for it