If you cannot place the order online then it won't work.

You only get the miles if the merchant pays the affiliate (CO or the operator of their mall) a commission on the sale. Each merchant sets specific rules as to what transactions qualify and what the rates are that they pay. The affiliate then calculates the appropriate conversion from that rate to the cost of the points (keeping a bit for themselves, of course) and fixes the numbers for the mall. Depending on the rates the different carriers negotiate for the points you'll often see very different numbers for the same merchant across different FF programs.

If you want to read a bit of a more detailed explanation on how the programs work (and why they seem to break so often) I wrote a somewhat lengthy screed about it earlier this week.

If you want to see a comparison on earning rates for a few different programs from the same malls I compared 10 merchants across 5 airlines a year ago. The results of that comparison are here.