Holepunching through CG-Nat, is it possible

Hi,
I have used ipfs with two nodes behind NAT on of the peers is behind a CG-NAT where it appears like it is double NATing the traffic,
The peers are unable to connect, the peers stay connected through the p2p-circuit relay and never upgrade to the direct connection.

I have used a python script called pystun3 to test the NAT type, it states that the NAT is ā€œfull coneā€ which should be the easier type but was never been able to connect.

Are there any techniques that can be used to test/bypass CG-NAT?