I have a website where I want to verify a user owns an address. There will be no purchases on this site. I just need to drop the address into a file and know the user owns it. I looked at How to verify MetaMask account holder is the real owner of the address?, amongst other similar articles. They all rely on the JS API. A malicious user can overwrite ethereum or web3 in the browser to trigger my callbacks that are listening to what I'd expect from MetaMask. Then I'd say they own this address. I took a look Verifying if a user actually owns the address which made me realize there may be a backend way to solve this, but I don't use .NET.
Is there a way to use metamask in conjunction with a backend that can verify the user owns the address? Is Nethereum the standard answer and/or is there a similar library for Nodejs or any other languages? I saw https://www.npmjs.com/package/nethereum-codegen, but honestly don't understand what I am looking at.