None of this was your doing
What actually happend was that Google decided (rather unilaterally) to deprecate certain APIs that we used in the Axiom Air app and, in so doing, remove all apps that used said APIs.
We ended up rewriting the app from scratch and resubmitting it to Google for approval.
That also explains why the newer version of the app would say "Install" instead of "Update". Its really a brand new app and you can safely uninstall the old one.