The key to flushing is that it just removes the chemicals that are in the soil and gets you back to square one. Then you can start back over with feeding them at a lower rate and gradually build up to where they are happy. Even if the nutes are not the problem, if it is just a chemical bind up from mixing the bloom nutes with the bug treatment, then flushing will clean out everything and that will allow you to start back with just bloom nutes. When you flush, be sure to use 2-3x the volume of water as the volume of soil. So if your pots are 1 gallon then you would use 2-3 gallons of water to flush, iff pots are 2gal then use 4-6 gal of water, etc.
After flushing them, allow them to dry out pretty good for a few days and then go back with 1/4Tbsp for the first 2 feedings. I personally prefer to feed less amount of food more often than a lot of food less often. Like 3 smaller meals a week rather than 1 large meal a week. It gives the plants a chance to absorb it without causing a toxic buildup.
After the ffirst 2 feedings then if they respond well and don't show any other problems, you can up the feeding to 1/3Tbsp for 2 ffeedings, then 1/2Tbsp after that. Doing it that way will allow the plants time to recover from what ever the damage was and then begin to feed itself again. Also, building up slowly will allow you to see if the recommended nute dose was the problem or if it was a chemical interaction problem.
Now the damage that you have there will not go away as it is beyond repair. I would suggest that you take scissors and carefully trim off only the brown, dead parts so that you will be able to tell if there are new issues or not over the next few weeks.