That's a pretty cool idea. Presumably if the Peachy's amplifier has a pretty tight band-pass filter on it then you might be able to do something like that.

Obviously scale would be completely messed up. The X-Y scale depends on how high the Peachy is above the resin (which depends on the installation) and the Z scale depends on the drip rate. However, many objects (eg. a 3D model of a face) would be recognisable even with very substantial scale errors.

I suspect the bigger indicator that there was extra data embedded would be the length of the track - for a nice Peachy print you'd probably have tracks at least half an hour long. That'd be suspicious when most tracks are more like 3 - 5 minutes.