Hello,
I'm trying to simulate a piggy back shattering with some coins in it. My original plan was to simulate the piggy bank and cache it. Then sim the coins with in the bank once it was cached.
In the mov file enclosed
video 1: is the piggy bank simed
video 2 & 3: my attempts with siming them together.

Is there a way to cache out a simulation, and have another simulation interact with that cache?

cant look at your hip now, but just sim your bank like normal, and cache out the geo with a file sop or rop driver. then for your second sim, use the cached out geo as a static object with use deforming geometry checked.

I looked at your file and almost everything looks correct
no need for 2 sims
you have collision relationship setup Left Affects Right so you don't have to worry about coins influencing piggy if that's your intention
or if you just want them not to break the piggy just exclude them from Impact group on fractureparms

the only 2 things you need to change are

1. use Reverse SOP to invert poly normals on your piggy since they are flipped now and that's causing lot of collision problems

2. on piggy DOP Collisions/Bullet tab uncheck Polygons As Convex Hulls since it is hollow and you want it to collide properly not only as a convex hull

in order to make the break look as you want I advise you to try prebreaking it instead of using dynamic breaking, but if you find some magic setting with dynamic fracturing that looks as you want, then forget I said anything