I already got platinum but I still have like 5 to 6 dog tags missing (I still have these ??? on them). Or are you talking about emblems?
There are stars on the tags for each thing you do, for example one says I have killed 34/100 hidden bosses. I guess that would put 3 or 4 stars on the tag with 100 kills, but I didn't know if I get a hidden trophy for maxing out all dog tags. Other wise I will skip them.