Missed your post yesterday. Will try and answer today. . .
The metal lath is fastened over the moisture barrier to the sheathing. The lath is used to reinforce and secure the scratch coat to the sheathing. The scratch coat is applied to the lath and left rough to give the brick veneer a good surface to bond to. The veneer was most likely installed with type "N Masonry Cement".
This process is instead of install a full brick veneer wall. This process uses full bricks and would be spaced off the sheathing and secured with brick ties (metal straps) to the structure.