Whenever you're looking at that PurePath list you're only seeing the 100 most recent ones so the highest response time one probably isn't in that set of 100. Try to use the outlier analysis filtering to find the slowest ones before looking at the individual PurePaths so you're only looking at the slowest ones.
When you select that window in the chart, are you directly clicking on "View Purepaths"? If yes, Can you please add the response time filter on the purepath list page to have the minimum response time of e.g. 500ms and nothing in the max. Click Add filter at the top of the purepaths list and select response time. This will display Purepaths with response time of 500ms and higher. This will let you know if you have any purepaths with response times that high. Let me know if you see any purepaths with that filter applied.