Power Director 13 by Cyberlink will do the job at less than $70. It's a video and slide show editor.
With this program you can adjust a considerable range of settings including white balance.
I've never tried editing videos of more than 10 minutes but if you run into problems with videos of 30 minutes or more, you can consider splitting them into smaller segments (this can easily be done within this program). Remember that if you edit a 30 minute video, you will be applying the modifications to the entire video. This may not be a desired outcome considering the lighting and color variations within the clip.
Good luck
George

There are typically two things that kill a flash. A huge amount of use that is way beyond what most folks ever do will eventually result in the actual tube failing. It is unlikely you will ever see that. The other problem is heat damage.

Heat damage is almost always a result of too many full charge flashes in too short a time. This is a problem that can be much worse with certain types of batteries, and almost all rechargeable batteries have a greater risk. They commonly have a slightly lower voltage and a higher current rating (they have a lower internal resistance, so they can supply more current even at a lower voltage). If the battery results in sorter recycle times, there is a problem. Current is the culprit. It recharges the flash capacitor faster, which generates more heat. Do that too many times too fast, and most flash units will suffer fatal damage. (With freshly charged batteries, you can start popping the flash as fast a it will go, and the flash will die before the batteries run out.)

Newer flash units have internal sensing for heat, and will simply shut off until they cool down. If you expect that kind of use, look for one that has heat protection. It is going to cost more, though. And worse, just about the only way to use them is to buy two and switch units when it shuts down.

Bite the bullet and get another flash. But from now forward be aware that too much too fast will kill it.