My guess is you will be very lucky and cleaver if you can get the boat to where you can use it.
However, I have used a hot air gun to take dents out of a plastic bumper. Never really looked the same, but better than when I started.

That boat is most likely polypropylene. It melts at a relatively low temperature, so it will soften at around 150 degrees F. Not something you want to touch. So you will have to heat it by moving your heat gun around in circles in order to not melt it anywhere, while pushing with something besides your hand. A piece of wood will work, but you can't reach much except around the cockpit. Towards the ends, you might try putting screws into the hull, heating up the plastic, and pulling on the screws. But you will have to hold pressure until the plastic cools.

There are relatively cheap plastic "welders" you can get on line. Try Harbor Freight. That might allow you to patch the holes. You can also weld with a soldering iron - but it won't look pretty. The good thing about the polypropylene is it can be heated and cooled multiple times without the material falling apart

Good luck, I would like to see what you end up doing 'cause I'm skeptical, but you might as well try.