Praise be to Allah, the Lord of the Worlds; may His blessings and peace be upon our Prophet Mohammad and upon all his family and companions.
There are eight categories of the beneficiaries of Zakah which Allah Specifies in the Qur'an: "The alms are only for the poor and the needy, and those who collect them, and those whose hearts are to be reconciled, and to free the captives and the debtors, and for the cause of Allah, and (for) the wayfarer; a duty imposed by Allah. Allah is Knower, Wise." {At-Tawbah, 60}. Commenting on this verse, Al-Baidawi (May Allah have mercy on him) said: "The alms are for these eight categories alone….the poor is defined as the one who neither has money nor a source of income while the needy is the one who has money or a source of income, but it isn`t enough." {Al-Baidawi, 2/455}.
Narrated Ziyad ibn al-Harith as-Suda'i:I came to the Messenger of Allah (PBUH) and swore allegiance to him, and after telling a long story, he said: "Then a man came to him and said: "Give me some of the sadaqah (alms). The Messenger of Allah (PBUH) said: Allah is not pleased with a Prophet's or anyone else's decision about sadaqat till He has given a decision about them Himself. He has divided those entitled to them into eight categories, so if you come within those categories, I shall give you what you desire." {Sunan Abi Dawud}.
In conclusion, Zakah must be given only to the categories prescribed in the Noble Quran. In other words, it isn`t permissible to give it to other than them, even for the purpose of establishing a welfare or a voluntary association. Consequently, it isn`t permissible to give Zakah to the charity mentioned in the above question, as it isn`t one of the eligible categories. And Allah, The Almighty Knows Best.