I have had hermies/seeds at the bottom of the plants before without getting seeds on the upper portions. Good luck, you may not have as many seeds as you think.
I hear that. I have some strains that I can't figure out who the daddy is but usually it can be determined from taste. If you smoke the same strain for a couple of months it's hard to forget it's traits (smell, leafs, density, etc.) and find them in your "unknown" strains.