Connection timeouts are usually handled server-sided, not client-sided. That means that this is a problem which should be fixed by the developers themselves. I have not read their sourcecode (and I can not), but I doubt that this is a particularly difficult code change to make on the server-side (but I could be mistaken - this is very hard to judge from the ...
Short answer: No
Theoretically you could if you knew the networking protocals that are involved and managed to compile a compatible version of the game with your fixes and got everyone in the game to swap a few DLL files.
But realistically this is only something that the developer can do as they are the ones that have the source code and control ...
If you haven't solved this yet I ran into the same problem and the solution is stupidly simple:
Unpack the symbols.zip file and repack it.
You'll hopefully get an ok sized symbols file. It seems that Unity is simply very bad at compressing.
Rename the compressed file to the same name as the original file