Work with controlling temps, and yeah, they were probably correct.
Your plants are doing very well generally. Try and accept it.
Has the crucified one recovered?
Try some annointed oils with kelp meal top dressing as soon as she looks better.
Careful messing with lighting too much, you can end up causing hormonal changes you won’t really like. Work back toward what you had prior to this and introduce cooler air from outside if needed (if possible).