Hi Jessica -
I would keep trying in Marketo- I had to do something similar the other day (correct a Lead Source Detail). When you ran your campaign, were there actual results listed? If not, you'll want to check these fields in your Admin set-up to make sure that changes are not blocked specifically for "flow change data value" - your campaign would run, but nothing would happen to the data set. Once I removed that specific block and re-ran my campaign, my lead source detail updated correctly according to my specifications.
Good luck!