Take a look at this question similar to yours which was asked recently:
Lost Electrum Wallet Password and Recovery Seed, you basically can't restore a wallet without a seed and can't access an encrypted one without the password. You can try one of the wallet recovery services as mentioned in the link but you will have to trust the service to not steal your funds.
Even if he trusts one of the services if he does not know the seed not a chance of recovering it via that, he would need an idea of it or it becomes impossible. If he trust's them it might be possible with copy of wallet file, and you would need an idea of password.
If you used something random, or have no idea what it is chances are pretty slim of recovery. But if you know part of password, or parts they can make custom wordists and you stand a much better chance.