I wasn’t clear – is the_title() actually set but just not displaying in the map? For example, if you print it instead of trying to map it, do you see it has a value:
What happens if you just hardcode the map title, e.g.
…title => ‘hello’…
If that’s not the issue, you could take a look at the poi template file to see if perhaps it’s not generating the HTML the way you need it. The file is: