If you check the readme included in the 4.84 mod, you'll find that Igiss created the hostilities between Rhienland and Liberty. The Embargo was an RP follow up.
If 2 countries are hostile and have an Embergo against each other, why would they let random tanks roll right on through their country?
And secondly, if you're a freelancer, like to explain why the Rhienland military, with it's reduced fleet after the Nomad War, would sell you a Gunboat? Might want to think about that.
Finally, it sound's like you picked it becuase it's possibly the best GB in the game, so it's a PvP vessel... That won't go down well on the forums.