It would likely take more than your hands. And you'd want to use something more focused to ensure it bends only where you want it to bend in any event.
An excellent way to make up clamping pads to support and lever on the tubing with is to drill very slightly undersized holes through some wood and then saw down through the hole along the grain so that you split the hole. The two sides of these clamping forms, or cauls, are then clamped securely to the tubing and then you can apply pressure to straighten the stays. The wood will ensure that there's no harsh point loads and with a bit of time, thought and elbow grease you should be able to straighten the stays out nicely. The good part is that because you're clamping the tubing right next to the bent area you're not going to put any bending stresses onto any of the bonded joints. So assuming the stays are steel (tested with that trusty magnet) then straightening the stays so that the frame is useable should not be all that hard to do. Just go slow and think it all through. You may also need to buy a couple of specific sized drill bits to produce the accuracy of the holes needed to ensure that you support the tubes well. A hair undersize, like by a1/64'th or less and let the wood "bruise" out to an ideal all around fit during the clamping is much better than going over size and having the clamping cuals put more pressure on only the clamping axis. If the fit does end up a hair loose despite your efforts a slip of business card or file folder card stock can be used to shim to an ideal push fit to get the cauls to properly support the tube.
From there build it up and ride it a lot for local short rides for errands. If you don't notice any issues with the bonded joints or other frame related catastrophes start riding it a bit faster and harder along with regular inspections. If it's passing all those tests then do some longer and harder rides on it. The point here is that you don't want to trust it at first so you ride a little slower and do frequent frame inspections. As it builds up a level of trust you can ride it harder, faster and longer in steps along with the same frequent inspections. At some point it will have either started to crack, as indicated by paint failures or other clues, or it will have earned your trust and you'll have yourself a useable frame. Whether or not it turns out to be useable for racing will depend on how you feel about it compared to some other frames by that point.