Not necessarily, "taken into account" from McGraw Hill means:

take something into account and take something into consideration:

to consider something to be an important factor in some decision. We will take your long years of service into account when we make our final decision. You can be certain that we will take it into consideration.
take into account - Idioms - by the Free Dictionary, Thesaurus and Encyclopedia.

If it was mandatory to take it into account don't you think they would have just said WILL INCLUDE instead of WILL TAKE INTO ACCOUNT?

For example, they can't include a status and category for furloughed pilots, because they don't have either. Although they must consider it, they have to ignore it since it's not pertinent. The basic reason behind the policy is to make it fair, not to mandate to the arbitrators how to do it. If that where so we would only have a brief discussion on career expectations since longevity and status and category are objective.

From reading the transcripts I think the arbitrators are smart enough to figure out what is fair. Man, I sure do hope so anyway.