Totally understand.
With the exception of rabies, my girl had her last vaccine in '07 at age 6ish.
The timing on the ones given just was not good. Since not all dogs respond at 12 weeks to vaccines, those ones almost have to be taking out of the equation because it has been too long (in between 12 and 20 weeks). One shot alone at 20 weeks could be enough, but most vets would want to do another one 2-4 weeks later to make sure. If not, then a titer would be highly recommended. If they would have only given one at 16 weeks, you wouldn't have to deal with this now.