Trampolim com carga

Um Mammont Rider PRC pode escolher entre vários montes, alguns dos quais têm Trample Monster Ability:

As a full-round action, a creature with the trample ability can attempt to overrun any creature that is at least one size category Smaller than itself. This works just like the overrun combat maneuver, but the trampling creature does not need to make a check, it merely has to move over opponents in its path. Targets of a trample take an amount of damage equal to the trampling creature’s slam damage + 1-1/2 times its Str modifier. Targets of a trample can make an attack of opportunity, but at a –4 penalty. If targets forgo an attack of opportunity, they can attempt to avoid the trampling creature and receive a Reflex save to take half damage. The save DC against a creature’s trample attack is 10 + 1/2 the creature’s HD + the creature’s Str modifier (the exact DC is given in the creature’s descriptive text). A trampling creature can only deal trampling damage to each target once per round, no matter how many times its movement takes it over a target creature.

No entanto, o piloto pode também possuir a habilidade Charge Through:

When making a charge, you can attempt to overrun one creature in the path of the charge as a free action. If you successfully overrun that creature, you can complete the charge. If the overrun is unsuccessful, the charge ends in the space directly in front of that creature.

É possível usar este atropelar como um elemento da carga e isso ainda seria uma ação livre? Isso faria com que o inimigo fosse pisoteado para ser derrubado? Além disso, isso significa que a cobrança não pode ser interrompida por uma tentativa de superação sem sucesso? Por fim, isso impediria que qualquer um dos atropeladores (o montanhista ou o cavaleiro) atacasse normalmente ao final da carga?