I recently ran into a situation where I needed to find users who made it to the end of a particular sequence in an email campaign.
I found this helpful article with the answer (see item #2).
To find users who made it to the end of a sequence:
Marketing > Reports > Campaign Contacts
This will give you a list of everyone who has made it to the end of the sequence.
Queued users are those that made it to the end but didn't progress to another sequence.
Done are those that finished and progressed to another sequence.