You can, and the rejection email even provides instructions for how to do so.
And where will you get the current list of all forbidden functions/APIs, not just those for this specific case with Electron?
Whatever symbols are found in the public header files in the /System/Library/Frameworks. Iirc, there are tools which look at a binary's used symbols and compare them to those headers.
Of course you can! How do you think Apple's checking your binaries?
Using some internal tool.
No, it’s almost certainly just a search for strings and looking through the symbol table.
That would be very easy to work around with dlopen and some string obfuscation. It's probably a bit more involved.
In practice it is pretty easy to slip things past the automated checks if you try to, which is one of the reasons they threaten you with a permaban for doing so.
The internal tool is very likely using/parsing otool / ldd output and similar. eg cli tooling that comes with macOS itself
exactly. Apparently Apple just started now to check against these private APIs.