I would recommend you not give this information over, as he will  probably unissue your refund and might ship you a miner instead.  Or he could just keep your money and miner.  They are sneaky like that.

I got a fun game!  Why don't you give us your btc payment address so we can see how many sales you have had coming in in the last 4 months, I bet its pretty close to zero!  If your chip is so efficient and good, where are all your sales?

Also, shipping a miner to your reseller and one to your lacky David doesn't constitute shipping.  People didn't pay for chips, they paid for miners that you promised and under delivered.