The map can only handle two values - in this case, you want tip_country_name and your "one", which is a delta_duration.
Add this code immediately before the last line in your query
table tip_country_name one |
rename one as delta_duration |
This would have worked, but the stats part is unnecessary overhead.
Try inserting this as the next-to-the-last line and see if the geom is picking what to display automagically from the last stats command it could see...
stats first(one) as delta_duration by tip_country_name |
I've used your standard of putting the pipe at the end.