Currently there are two sets of Rank 9 Sicarios. The weapons and guns only go up to Rank 9 so it leads people to believe that when you unlock Rank 9 sicarios that they won't get better and people invest alot of money in gearing teams to find out later that there is another group of Rank 9 sicarios.

Is there a way we can highlight to people there is another tier of Rank 9's they are able to unlock? 

As far as I'm aware it's not the case with any other Rank and the only way people find out is either when it's too late or someone who has made the mistake before has informed them and it can be a very expensive mistake to make but the game doesn't actually tell you or let you know.