I left for out of town the morning before you private messaged me with additional photos or I would have replied sooner. It might be best to post supplemental photos directly into a thread because the more people getting a good look-see, the better. Private messages hide them from public view. The beauty of forums is that one hopefully gets lots of good leads to follow from more than just one other gardener.
The product you chose is an insecticide and a systemic to boot. It's going to kill off beneficials that may very well have been keeping opportunistic pests under some semblance of control. The Bayer Advanced Complete Insect Killer for Gardens supposedly states on the label that it controls the following:
Annual Bluegrass weevil (hyperodes weevil), Ants, Armyworms, Billbugs, Black turfgrass Ataenius, Centipedes, Chiggers, Chinch Bugs, Cockroaches, Crickets, Cutworms, Digger Wasps (Cicada killer), Earwigs, European crane fly larvae, Fire Ants, Fleas, Grasshoppers, Leafhoppers, Mealybugs, Millipedes, Mole Crickets, Mosquitoes, Pillbugs, Scorpions, Sod webworms (lawn moths), Sowbugs, Spiders, Termites*, Ticks (including deer ticks), White Grubs (including larvae of Asiatic Garden Beetle, Black Turfgrass Ataenius, Chafers, Japanese Beetles, May or June Beetles, and Oriental Beetles)
* This product will kill workers and winged reproductive forms of termites that enter into the treated areas. Use of this type of product to kill termites should not be considered a substitute for soil treatment of subterranean termites done by a professional pest control operator.
Unfortunately, I believe you may have a fungus and a hard bodied scale problem and the product you chose will not treat fungal infections and does not list scale as being a pest it kills on the label although mealy bugs were listed. If you purchased the granule product, you might want to take a shop vac out to the area and suck up the granules. If you used a spray, might not be a good idea to spray again. Maybe wait a week or so and consider trying an appropriate horticultural oil spray combined with baking soda?
Also too, the active ingredient in Bayer Advanced Complete Insect Killer for Gardens is Imidacloprid. Imidacloprid is carcinogenic and believed to be "weakly" mutagenic-
The other active ingredient in the Bayer product is Beta-cyfluthrin. That's a suspected endocrine disruptor and is toxic. It may be determined to be carcinogenic as well as a ground water contaminant at some point in time.