I guess we'll go back and forth with this, but again, how would any league official, or any USBC official know whether something in a bottle is legal or not? They won't, so they will either, 1) give approval (most likely) and just add a useless step for all bowlers, or 2) deny cleaning of bowling balls, thus rendering all their prior research useless...
The dishonest will ALWAYS find a way to cheat. It is impossible to "legislate" honesty.