From best I can gather the upcoming waiver draft has nothing to do with these players being released on waivers, Carolina could have just left them exposed and lost them there unless a deal has been made with another team to re aquire them.
However, it's smart on the Rangers part because a team can only lose a maximum of three players at the draft unless more are offered or at the time of the draft they acquire another player and are forced to expose someone else. With these two players being added prior to the draft, it lowers the percentage of their regular roster players being grabbed and especially as in the case with Hereema it's unlikely these players won't be grabbed by someone else.
There "could" be a third team in the mix such as Pittsburgh or Nashville who have agreed in a back door deal to get these players back to Carolina in exchange for future considerations (for example).
Just MO.
