i have big feet and i have this problem on smaller machines. i tend to find myself using my toes to push the pedals and not the whole foot. im not sure if an ideal solution exists.

An age old problem I'm afraid, some trucks are worse than others due to the close proximity of the pedals.

The only thing you can do is to trial various brands of safety footwear and see which ones are best in this situation.

The potential for this to happen is something that I always cover during operator training, citing it as one of the reasons to always allow plenty of time to stop, and never to rush towards anyone or anything.

What model forklift was this? If it had an inching petal, that you use your left foot on, they should have been able to control any movement even if the throttle was unintentionally pressed. I saw this happen when the operator with huge feet didn't have his left foot in position ready to go on the inching petal and his right foot got jammed up on the throttle and he went flying backward and put the counterweight through a wooden 2X4 wall. It was operator error.