I'm sorry, but the algorithm for detecting climbs is slightly complicated and as an automatic algorithm, there's no guarantee that it fullfils everyone's expectations.
I understand your issue and - to be honest - the climb detection surprises me, but we can't put effort into single cases.
We do have some open issues that might help for what you want to know (VAM of a specific part) and you might also raise a feature request to analyze a climb by simply selecting the part in that view.