DO you have a very high ball speed or a fairly low rev rate?
The Black Pearl is a fairly aggressive coverstock on a high differential core. I can hardly believe you were able to use it on medium-dry lanes with that strong a surface: P1000 grit + light polish.
Its stock surface is P1600 grit FEMA (800 grit US.CAMI, a light grey SB pad) + a high gloss polish application. With that it's meant for medium-heavy oil for an Avg rev rate, avg ball speed bowler.
I suspect the drilling and the surface is too strong to play down and in. Try a smoother finish with more polish, maybe P2000 grit pad + a good dose of polish. Alternatively, try a flare reducing weight hole.
"None are so blind as those who will not see."