A month such a short time make take months or years to recover.
Agree, the wallet would need to be "brute forced" cracked which is currently not an option for bitcoin wallets, especially if it was more than a handful of characters long. The bitcoin wallet encryption is strong by design. To brute force, we need to be able to do millions of attempts per second. This is currently impossible for the bitcoin wallet. A general quad core i7 computer can only makes 10-13 attempts per second.
However, if we have a good idea of the password (and also the length of the password), then it won't take months or even weeks to break it. Hopefully, he knows what the password should have been but maybe he is one character off or the capitalization is off. These common mistakes are the most likely reason that he is locked out of his wallet. Dont be worried, I can offer you some helps.