Yes that's all there is. AFAIK there is no central registry of tokens, and duplicate symbols can be created. In fact, some smart contracts have already been hacked by creating a fake "EOS" token:
https://thenextweb.com/hardfork/2018/09/18/eos-hackers-exchange-fake/
for example.
You can create a VM on Virtualbox. This virtual machine will run Ubuntu. It should work fine on your Windows machine. You can workaround it (maybe) by using the Ubuntu subsystem which you can install in Windows, but I think that would cause more hassle than it's worth.
Is there any particular reason you don't want to use a VM running Ubuntu?
>EOSIO based blockchains execute user-generated applications and code using WebAssembly (WASM). WASM is an emerging web standard with widespread support of Google, Microsoft, Apple, and others. At the moment the most mature toolchain for building applications that compile to WASM is clang/llvm with their C/C++ compiler. For best compatibility, it is recommended that you use the EOSIO toolchain.
So yeah, that's the definitive answer. If you can find a compiler for C# to wasm you're gucci. Essentially any lang that has a compiler to wasm is fine for dev. JS should have one. idk about C#.