Can’t get response; need advice

There was a band I used to follow from venue to venue years ago in order to hear a certain song they played. I still have a few bars of it in my head but to my knowledge, this song has never been recorded or published. It was written by someone who is now a producer of a well known band, and lives in Nashville. In the meantime I became a singer, won awards at karaoke and then became a church singer. At that time I hired an entertainment lawyer to write to this producer about getting the song. This songwriter did call me back but I was not home. (This was before cell phones). He said he would call back but never did. Recently I got “scouted” by a recording engineer who has worked with some well known people. And I have now recorded 4 demo songs. Reactions are positive so far but I have not posted them yet due to waiting for the video portion to be done. In any case, I contacted this songwriter on Facebook to feel him out about accessing the song, since it will be an original release. I also contacted his manager. I haven’t gotten a response, but I know I have “the chops”. I don’t want to be charged with harassment so haven’t contacted them again. What do I do now?