My initial thought is you might be mistaking terms..
DTS Packages that are migrated are turned into SSIS packages and therefore would not be under the legacy DTS packages they would be in the SSIS package list.
Migrated DTS packages almost always need some TLC before they are "right" again.. There are only a few packages that do a good job with them DTS xChange is one of the best.
So the question I have is what did you do to the jobs and what was your expectation of whatever you did?
CEWII