Connection to balanced Oracle DB

I have to work with a client's infraestructure, and in the dev environment they have an instance only Oracle DB wich works perfectly with the VPN connection and Datagrip.

I'm trying to connect to their qa environment where they have an Oracle balanced (3 nodes) DB service trough Datagrip with the same VPN, but i get this error:

Connection to Oracle [noraui] - @mnbdqa001-scan.naiss.local failed.
[08006][17002] Error de E/S: The Network Adapter could not establish the connection

Just in case you think I misspelled the host info... the domain is reachable, that is not the problem:

ping mnbdqa001-scan.naiss.local
PING mnbdqa001-scan.naiss.local (172.20.8.21): 56 data bytes
64 bytes from 172.20.8.21: icmp_seq=0 ttl=253 time=7.893 ms
64 bytes from 172.20.8.21: icmp_seq=1 ttl=253 time=6.788 ms

I used the same configuration that i used on dev connection, but pointing to the balanced service, but it doesn't work.

Is there any reason for this to happen?

Additional info: I have a Java app running in my notebook, connected to that balanced Oracle DB service that works fine, so it is not a network configuration problem.

I don't want to use Toad, i prefer to keep using Datagrip. Please help!