I'm sorry it has not improved for you. The roots must have been pretty seriously compromised.
The growing tip on the failing plant has died so that plant will not recover. You can cut it down, but don't try to pull it out as that will tear the roots of the other plants.
There is one plant that looks healthy and seems to be putting out healthy new growth. That is a good sign! You might want to physically push that plant more to the upright vertical position to make it lean less. Press the soil down tight around the base of that plant to hold it in position so staking won't be necessary. The third plant is borderline and may or not make it. Watch for signs of healthy new growth as the best indicator of its future. It, too, can be pushed to the vertical.
Make sure you are not overcompensating and letting the soil get too dry.
