Hi Bob,
As I understand it, and I could be wrong, the Andy Laverne soloists have restrictions placed on them by the performer. Once, quite a while ago, they were included in a $49 BonusPak. As far as I recall, though, that has only ever happened once. Since that time, these soloists have been sold as separate items. (This is one of the reasons that I always install new versions of BIAB over the top of existing versions -- just in case I have something from a bonus pack that I'll never get again!)
I did a little research and if you go to the link below, you'll find the MIDI Soloists sets that are included with the UltraPak and Audiophile BIAB editions. Sets 12 - 15 are not included in this list.
https://www.pgmusic.com/addons.soloists.php?os=winBy comparison, the below MIDI Artist Soloists (i.e. Sets 12 - 15) are listed as available for sale but not included with any BIAB packages.
https://www.pgmusic.com/addons.artistsoloists.php?os=winRegards,
Noel