I called up a trusted vendor (not where I got this orchid) and had a lengthy lesson on scale and treatment. Here's what I've learned so far:
* The scale infestation looks worse after I sprayed the Malathion, because the spraying upset them so they are coming out from their hiding places (medium, within the dried areas of the pseudobulbs, etc).
* Neem oil will not do much to help me when the infestation is this great. I will need something stronger.
* Scale also lives in the medium, pseudobulbs dried sheaths, leaf crevices where I can't see in addition to the front and back side of leaves.
* An infestation this great will mean I will have to keep up with spraying and treatments for at least 2 months. Even after 2 months, I will have to keep a watchful eye in case any survive. Scale is like mice. Once you see one, it means you have close to 10.
Recommendation:
* Use
Bayer Advanced 3-in-1 Insect Disease & Mite Control at full recommended strength and spray once a week.
While he personally has not used it as a dunk, I am going to mix the recommended bottle dilution in a bucket and dunk the whole pot to the top of the pseudobulbs for about 5 minutes, let it sit for about 20 minutes to let it soak in and work its magic. Afterwards, I'll soak in water and do multiple drenches to wash it out. I will follow this up with spraying the rest of the leaves.
I'll do the dunking once a month and the spraying once a week. Hopefully this will work.