If you finished all the stages that were run for the event, then you should have 'finished' the event. I can only wonder if you failed turn in your timecards somewhere later, in order to be scored. If that is the case, then you did not finish.
Assuming you did all the right things, and really were scored, then you officially finished, and should be seed 7, along with the other seminar, as long as it is counted as a 'school' as mentioned in the rules.
I would keep any documents that show you officially finished this rally, and any evidence of finishing the school, to take to the next events. If you are listed as seed 8 there, you should be albe to get that corrected at the event to seed 7 if you can show the evidence.
Also, check with the 'keeper' of the seed list (Is this still John McArther???), to make sure your seed list on the SCCA Performance Rally site is updated.
Mark B.