If you grab JUST chillrend, you should be good. As far as I know the sword isn't related to the TG quests besides location.
Yeah I saw Mercer's Orders and the other stuff that requires you to grab for the Questline. I've decided my Dark Elf is just going to wait on it.. for now.
My Nord however, whom is LV50 is about to go grab it. This sword fits him perfectly, PLUS Chillrend is leveled. IE. If you get it past LV46+ it's even stronger then a DAEDRIC Sword. Check the UESP if you don't believe me lol..
<3 Wiki.