There are fixes. They involve a bench vise, knowing what you're doing, and knowing a little about the ins and outs of bending metal at a weak point which has developed "spring memory" over more than half a century.
Pad the vise, clamp the blade so the bend point extends beyond the vise jaws by about a millimeter. It's likely that the bend is at the intersection of tang and blade, right at the ferrule. If so, clamp the knife so that the finger guard is outside the jaws but pressing against them. Use the handle to gently bend the knife, in one direction against the bad bend. Don't bend more than a couple of millimeters at a time, hold the pressure for a minute or two, then release it. Checking your progress frequently, repeat the process until the bad bend disappears. Do not remove the handle or heat the knife. Do not rush the process. Wee, tiny, itsy-bitsy baby steps -- one at a time. Slowly slowly catchee monkey.
However, returning the knife for a straight replacement is a MUCH better idea. Bent Nogents are a known problem, and you should have contacted TBT before purchasing and told them you wanted a straight knife to begin with. Now that you have one, you should contact them (her, actually) again. Call (as opposed to e-mailing) The Best Things, explain the problem courteously, and arrange for an exchange if possible.
You should not have to pay tax or customs for a "free" exchange, but you will have to pay shipping. Contact the post office, or customs or whoever sets the duties and/or taxes in wherverthehell you are and find what they'd like from you in order to just pass the knife through without assessing further charges.
Say hello from me to the nice lady at TBT. It may not help, but it won't going to hurt either.