When starting game you will still have to deal with game trying to connect to server and will have to wait through it as it fails. However, Unsuccessful server connection attempts "PLEASE WAIT WHILE WE CONNECT TO FAR CRY 3 BLOOD DRAGON SERVERS" when you pause and go to menu are mittigated by doing this.

Go to <path-to-game>\bin.

Open FC3.dll and FC3_d3d11.dll with a hex editor such as HxD. https://mh-nexus.de/en/downloads.php?product=HxD

Use Hex Editor Search to find Hex string FF 89 43 0C 85 C0 74 30 83 EC in both files and change their corresponding 74 hex values to EB.

Search for 8B 53 0C 85 D2 74 30 33 C9 in both files and change their corresponding 74 hex values to EB.

Save your changes.