Zakat

Calculate the goods at stock, its profit and the cash you have and give 2.5% over it

The most  authentic opinion is that you pay zakat on all types of gold.

If she’s poor and needy, yes.

She is the owner of the gold and she is responsible for paying for the zakat. If the husband is willing to pay it, this is a gift from his side.

As long as he is volunteering, this is accepted and sufficient.

This is not permissible as zakat must be given directly to the poor and he may do with it whatever pleases him.

What he is saying is totally baseless. First of all, the nisab of gold is 85 grams. Secondly, the zakat is paid over the whole amount. This means that your zakat is 5 grams of gold.

Zakat can only be given in cash to the poor and needy. If he fits the description, you can give him from the zakat.

You give Zakat on whatever gold and silver, and money you have in your bank account at the end of a lunar year. Money is treated like silver in regards to the threshold which is the value of 595 grams.

Zakat has to be in cash or they authorize you to buy them something specific.