If you have a few meetings with a professor to discuss a paper, but they do not do any actual writing, is this sufficient to justify authorship?
The content of those meetings is largely going to be the answer to your question, and we can't really know the content of those meetings. There's a case to be made that those discussions helped form things, and he doesn't sound otherwise problematic, so I think it's likely worth just making him an author and moving on.