I can give the OP the information that they might need to get in touch with the copyright holder to Bill's songs. Second, I am in the USA which has a totally different set of rules regarding recording of copyrighted material. As someone who is NOT a publisher (nor a lawyer) but does record a lot of copyrighted material I can speak to this.

JHW is correct above, but in the USA, you do not need permission to record copyrighted music. You *are required* to pay a mechanical licensing fee if the song will be released commercially.

I try to deal with the copyright holder directly. If that is not possible there are several websites that will do a copyright search for that person. In one instance I could not get a response from a license holder so I just went with a website called Easy Song License

Besides paying for the privilege to release a song commercially, it's also the right thing to do.

Deb Cowan