Not sure what strain your growing, but switching backwards and forwards in to flower and veg and flower probably isnt a good idea. Growing indoors is different to how the plants behave outdoors. Yes is true a mature plant will flower abit faster than one forced into flowering, and mature cuttings is the best way. Some strains take different times indoors to go into flower. Ive seen some pure sativa take 9-10 weeks umder 10 on-14off lights to even show one pistol. Usually for most indoor hybrid strains its 3-4 weeks. Also its probably a good idea you put more holes into the bottom of your pots so the media can actually drain. Two tinny holes isnt sufficient. And you want your pots slightly raised from what ever they are sitting on so that a bit of air is able to circulate around the bottom of the roots. Its because of these things your probably getting root rott. It will probably be a good idea to get some h2o2/oxeygen plus products. And add that as directed regularly into you plant feed, it should help fix the rott. Perhaps a good idea to mix som h2o2 with water and wipe down all your surfaces once or twice . That should help.
I dont even think you should be use a humidifier for a couple of plants. Lots of grows on here you can see that do fine whithout them. Its just going to cause you a risk, and if you arnt experienced your going to have problems. Keep it basic, light, water (with feed in coco/hydro) and fresh and moving air.
