"Codes for this product are temporarily out of stock" :/
you should not wait to get humblebundle keys, it is a bad idea.

Ouch, why is that... Very sorry about it, do you think it is realistic for them to provide a key or should i look to obtain a key elsewhere?

Edit: Trying to get another one right now and update this GA with a working one ASAP, pardon for the inconvenience.

Okay, edited the key entry, if possible to check it out please when good for you, hope it works.