TCP traffic and ping

Our databases are 12.2 and run on Linux Database Servers.  Our listener uses dedicated servers over TCP protocol.

We have two applications, each installed on a different Windows server.  Recently, our network team implemented an “isolation network” and placed those application servers inside of there.  Since then, the application just “stops”, and they’ve taken to rebooting in the Windows way.  Sometimes, but not all the time, I see a tns timeout in the alert log.  I’m trying to follow along on the backend, but mostly I can only say “database is working”.  I hate that answer, but information is hard to come by.  When I ping either of the application servers from the Linux database server, it just