Yeah, I've boiled them for a minute, I've sanded them with sandpaper, I've done different stuff and had no success. I've dug up seedlings that are still alive and growing, but nothing from the seeds.....What I do for bluebonnet seeds is to nick them with scissors. Might work on redbud.
No, the seeds I collected had already gone through at least one Winter, as the pods were old and brown and were on the ground. I did that thing where you boil them for a minute and soak them in green tea and then put them in damp paper towels in a baggie, but the germination time is so long, like Crackerbee mentioned, that mold set in eventually. I tried mixing a bit of bleach with water to get the paper towels wet but mold still set in.....then I did the boiling and sanding and just put crumbled and dampened manure in ice cube trays and put seeds in the manure and put everything in an incubator set at 80 degrees or so, and kept it moist and humid for a couple months, still nothing.....Have you tried freezing them?