Interesting , actually it should be other way around. (see the following blog post , there we have a different behaviour ->
https://ermanarslan.blogspot.com/2021/01/ebs-122-configuring-application.html)
You may check the relevant template file and see if there is some casual connection there. (your AD & autoconfig version may also be the cause) .. Check the template and try to predict where the autoconfig takes that value.. (db parameters maybe.. Local and Remote listener parameters I mean..)
Also, s_jdbc_connect_descriptor_generation is also important.
if we set it or leave it as is (I mean if it is set to TRUE), then the apps tier autoconfig will overwrite the jdbc url with the scan-based & load balanced one. (but you are saying the exact opposite.. But still check that value)
Autoconfig may also take that value from the old context files stored in FND_OAM_CONTEXT_FILES table.. Check that as well..
In the worst case, you may clean up the network topology and re-populate it with autoconfigs(db + app tier)