Generally speaking, it's extremely hard to try a rape case. Even if you have DNA evidence from a rape kit, you need another provable circumstance (significant vaginal tearing, scars on the suspect from the victim defending herself, a friend saying she heard her yell stop, etc.).
I don't know if they have those in this case, but it's atypical in a rape case to have anything other than the victim's word and some vaginal redness.
On the other hand, while it's pretty hard to get a conviction, it's generally not that hard to get an arrest warrant. I'd worry about that if I were a Blackhawks fan (and I am). It doesn't take hardly any evidence to get an arrest warrant in a rape case, unfortunately. And if Patrick Kane is arrested on suspicion of rape, it won't matter if he's convicted. His career will be over, in my opinion.
That said, prosecutors don't typically want to file charges in cases they don't KNOW they can prove beyond a reasonable doubt, especially a controversial high-profile one.
With all that said, although we don't know much in this case, based on typical rape cases, I'd be surprised if Kane were arrested or tried in this incident. If they're waiting on labs back from DNA to decide whether to make an arrest, that tells me they don't have much, if any other, evidence,