I've looked all over as well without finding a single Micah McIntosh anywhere near Kentucky.

If he died fairly young before 1850 he may not have ever appeared in a census.

His widow may have been named Susan or Susannah

I've looked for a Micah Miller as well, thinking the story may be mixed up and it was Micah Miller's widow who married a McIntosh.

Thank you for trying to help me on this.