A photo would be helpful - it is possible that there has been a mix up (possibly as simple as having Gold Laced instead of Silver Laced) or your birds may have some extra smuttiness to their coloring due to the nature of hatchery stock.
Yes - *this* photo shows a bird that appears to be a cockerel. I would not expect to see a large comb at this age, but the amount of prominence that is showing and the color of what is there combined with the pattern showing in the feathering all point to cockerel. Can you get a photo of the...
Hmmmm......I am thinking this is either a SLW mix or possibly something entirely non-SLW related at all - rather than "lacing" this bird appears to have markings more closely resembling "spangles" (ie on the chest) - and even that is more just the closest word I can think off at the moment than...
??? Do you mean "straight run" (unsexed chicks)? Since the OP stated the chicks came from the "pullet bin" that would indicate they were, in fact, sexed - and for 3 of 44 to be mis-sexed is actually pretty good given that with vent sexed chicks you have 5-10% risk of a mis-sexing.