Shoving a Creature:
Using the Attack action, you can make a special melee attack to shove a creature, either to knock it prone or push it away from you. If you're able to make multiple attacks with the Attack action, this attack replaces one of them.... You make a Strength (Athletics) check contested by the target's Strength (Athletics) or Dexterity (Acrobatics) check (the target chooses the ability to use). If you win the contest, you either knock the target prone or push it 5 feet away from you.
From the description of Bigby's Hand, one of the options:
Forceful Hand. The hand attempts to push a creature within 5 feet of it in a direction you choose. Make a check with the hand's Strength contested by the Strength (Athletics) check of the target. If the target is Medium or smaller, you have advantage on the check. If you succeed, the hand pushes the target up to 5 feet plus a number of feet equal to five times your spellcasting ability modifier. The hand moves with the target to remain within 5 feet of it.
The Forceful Hand is similar to, but clearly not the same as, a Shove attack. (For instance, in a Shove, the opponent can choose to use Dex to oppose, and the Hand can push a creature much farther (5+5m feet where m is the caster's spellcasting ability modifier) than another creature can (5 feet) using the regular Shove action.)
The question is: for Bigby's Forceful Hand, can "in a direction you choose" include "earthward"?
Are there any developer rulings on this, and if not, how would you rule this at your table, and why?