Omissions of undergraduate information I am new here. I was wondering since many of you are learned professionals what your opinion on this is.

I have recently returned to further education (as an undergraduate) and have been there for a few years. In my original application to the university, I filled in the previous academic background section as much as I could. Since there have been a large number of years since I left a course I did not finish, I was wondering if - ethically and perhaps code of conduct wise - forgetting to include that I did not finish said course at a 'partner college' to the university I am currently enrolled at would come back with implications down the line. 

Would it be best to bring this to attention? It is worth mentioning that the results for which my current undergraduate course was deemed 'conditional' from, are not related this course I accidentally omitted. Any opinions?
You should have been asked for transcripts of all your previous work, and those transcripts will fill in what you may have omitted.