Fix Windows for an app to connect to Oracle db

I need to resolve an issue which a vendor provided us an web app that can connect from a windows machine to an Oracle database. It works from our vendor's environment but somehow it doesn't work in our environment. Trying to register the Oracle db for the app but it cannot using the database connection.

Attached is the windows trace file.

We can connect to the oracle instance using SQLPLUS and can TNSPING it but it is not having issues from the app that we need to install. Vendor says, something in our network environment is preventing it to connect.