Pay for it...
Sorry, but to get the password for this challenge, you'll have to pay for it.
Luckily, I was able to find some partial credit card numbers that you should use.
You should make the payment with all of them so it doesn't look suspicious.
Credit card 1 : 4??3-?41?-??1?-?6??
Credit card 2 : 55?9-?06?-??2?-?5??
Credit card 3 : 4??0-?29?-??8?-?9??
Challenge made by jcfs.