Mai ek company employee hoon aur

If the transaction is genuine and also in ordinary course of business and at Arms length basis then prima facie there should not be any issue as such ,there will be definitely a sign up / on boarding process happen for distributor appointment ...and mostly some due diligence will also happen ...now the two issue arises ;-
a ) You have to provide bank details of firm of your brother
b) if you are partner or proprietor of distributor firm and provide your bank details for crediting comission then on scrutiny they may find some suspicion

Better to show them all evidences from the inception itself and also said them about under what circumstances,they are demanding money back ...

if this is against their HR policy ,then you can pray for relief ( if everything is bona fide ) and update firm bank details ,also check that whether double credit is cause ,like in your account and also on firms account .

Write specific letter to your managers with all evidences and also a CC to appointing authority of distributor and see what happens...

Disclaimer - For education purpose only ..should not be construe any advice