I doubt the bent stems are affecting the plants. If I have a 'too tall' pepper plant, I will remove the lower leaves and plant it deep like I do with tomatoes.
Most plants will go through some degree of transplant shock and look wilty for a while, but you may need to shade those newly planted ones until they perk up a bit, since you say that they haven't been in the sun for a while. I guess you could call it "in situ" hardening off.

agreed with noinwi, remove the lower leaves a few hours or a day ahead of time, then plant the stems in deeper.

Tomatoes are planted deeper because the little hairs along the stem turn into roots and can help the plant. I haven't seen any of those hairs on pepper plants. Although most any plant can grow a root anytime it has a joint in contact with the moist soil. I have wondered the same thing for a long time. Anyone witness a pepper growing a root from a joint near the moisture?

I think in general it depends on how moist your soil stays.

I get a few Non bell sprouts that grow roots up to their seed leaf from the start.I read that people call them air roots...
I put those plants way deeper than some others.

If I get a leggy plant I'll plant it deep and watch the water for a week or so or it might rot.

Another option is to bend the plant down,above ground and force it to grow branches earlier.Once new branches start stake the plant straight up.

As far as Bells go,I'd put them about 3 ft. under in a compost pile.
I don't think that the work involved in raising a plant is worth only a few pods at harvest.
Non bell peppers mostly will out produce a bell any day.

There are a lot of better tasting,more productive,easier to grow non bell peppers that you can grow.
Not all non bell peppers are hot.
For instance a lot of the Sweet Paprika or Pimento pepper varieties are much more productive,grow like weeds and taste better than bells.

The wilting in the sun was probably caused by either shock at being in the sun(not hardened off yet) and the roots couldn't suck up water fast enough to supply the plant yet- not big enough to support the plant yet.
If you leave the plant in shade a week or so to let the roots develope and get used to the sun you should be ok.

The price you paid ,I agree would be hard to pass up.

I just have a dislike for bells after growing a lot of easier to grow non bell peppers.
I've never had harvests of non bell peppers as low as what I got from bells in my California weather temps.
Good luck with yours.

I've rooted some Bhuts that I had broken the ends off while transplanting.