Hopefully, Ken is correct about the problem lying in the brake light switch.
However, given the make, model, and model year of this vehicle, there is another possibility that needs to be checked out, a.s.a.p.
I am referring to the known issue of broken motor mounts and transmission mounts on this era of the Odyssey. If the impact with the curb was hard enough to snap these already-weak mounts, then you could have a situation where a broken mount (or two, or...) has slightly changed the position of the transmission vis-a-vis the shift linkage.
You really need to have a mechanic put this van up on a lift in order to check the condition of the motor and transmission mounts. Even if the current problem is not the result of bad mounts, given the likelihood of broken mounts on this type of vehicle, you need to have a mechanic inspect the motor mounts and transmission mounts in order to prevent other--even more serious--problems in the future.