Nick,
That sounds like a good effort. Fingers crossed that you have now fully sealed your pond.
I think I will have sufficient clay at my pond locations, but I am going to have to come out of the bottom of the pond with some lifts of sealing clay over some sandy layers at slightly higher elevations. My plan is very similar to what you performed on your pond!
P.S. TJ has LOTS of pond sealing experience, taking his advice seems to be the correct course of action in most circumstances. If your pond is mostly (but not perfectly) sealed, then he might be a resource to perform a Soil-Floc treatment if recommended.
Good luck having a nice sealed and water-filled pond in your near future!
