Could you post a few photos of your bow stave???
That way we can see where the starting point is.
Self bows don't have to be straight. That said, wood can be straighten by heating it.
Steam or dry heat from a heat gun. Both work fine.
When I started straighting bow staves I used a large cook pot, half full of water, on the stove and two small oak trees in my yard. Steamed the crooked spot for about 30 minutes. Wrapped the steamed spot in a old towel and then soaked the towel in hot water. Ran out the door like a mad man, slung the towel off and straighten the stave between the two trees.
According to my wife it was a sight to watch.
Hold it just past straight for several minutes. Then hit with cold water from a hose.
Works great.
David