Playing a evil High Elf, I went on a murder spree in every city in Cyrodill, including Skingrad. Long story short, I killed everyone in the Skingrad Mage Guild except the head lady who gives you the recommendation. I haven't started the Mage's Guild questlines yet, so (obviously) I wasn't expelled for frying my fellow mages.

But something just occured to me. When I usually do that Skingrad recommendation, she tells me where the missing guy is but doesn't know the cavern, so I have to ask the other mages there. Mages that are now, of course, dead.

So...um...did I just ruin the Mage Guild quest line? Could I still be able to complete it via finding the cavern myself or asking someone else?