who will probably show up fashionably late. The Manderlys are in White Harbor which is on the southeast coast and the other end of the continent from where they were recruiting, so it probably took some time for this house to receive the letter, deliberate the matter, muster a force together, and then travel.
I think the Reeds (Meera's clan) might also send a token force because Howland and Ned were close friends. Left of Ned in this pic:
This would also bring the one living character who was present at the Tower of Joy into the picture to support the eventual 'Big Reveal'.