Paying for one's divorced wife's expenses during her iddah period

If 2 people are divorced. The girl moves to another town. The ex husband tells his ex brother in law to ask a mufti in his area twice to ask how much iddah money I have to give. But he doesnt ask and says its ok about the money. But I said, no I have to give as its my right. Then he says ok. Do I still have to give? As my ex brother in law is a moulana and he knows its the right of the ex husband to give iddah money. He still didnt ask a mufti. But I gave for 1 month.