About the "Requires reflection to access the Fast Travel functions as they were made internal".
Have you tried to publicize the Assembly-CSharp.dll, with
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for example?
Code:
NStrip -p Assembly-CSharp.dll
This should set everything to public, so you can just mod the usual way, no need for reflection.
Then you can import publicized dll instead of original to your project and compile cheat plugin with it (need to enable "Allow unsafe code" in project configuration--Build--General).
Compiled plugin will work with original Assembly-CSharp.dll in the game.