Are you sure it was powdery mildew? Do you have any photos of it? I don't think I ever saw powdery mildew on Hobbit or Gollum, but that doesn't mean it couldn't be.

Baking soda+vinegar sounds bit strange to be used on plan. Did you keep plant out of sunlight while spraying? I see some white 'dots - spots'; is that residue from your homemade sprays?

Plant looks rather thirsty to me. What kind of substrate is it potted in and how often/how much do you water?

Did you follow this recipe or try something stronger? Vinegar by itself can harm the leaves.

Homemade Fungicide Recipes

Vinegar is often an ingredient in recipes for homemade fungicide spray. Huntington Botanical Gardens recommends a spray made with 1 gallon water and 1 tablespoon each of baking soda, horticultural oil and vinegar for treating black spot and powdery mildew, as long as the temperature is under 80 degrees Fahrenheit. However, according to University of Kentucky experts, few organic remedies for treating fungus, including apple cider vinegar, have been studied with "adequate checks."

Thank you both

So yes on the first comment the white dots are the leftover mildew. I water about every 10 days and it's planted in a succulent/cacti soil with plenty of drainage. The mildew came on when the heat and humidity in the office changed drastically.

On the second comment I followed that recipe pretty closely except on another blog it told me to add a non acidic hand soap instead of the oil. They told me to alternate between that recipe and a diluted milk solution - one week apart

As soon as I sprayed on the recipe above, the mildew stopped spreading. But after the second baking soda treatment it started to wrinkle and shrivel. So then a week later I tried the milk and it got a little worse.

I thought maybe I should have watered it before I started to treat it. So this evening I gave it a good watering. I'll stop treating it for a while and see of the mildew comes back

Not sure where you read the recommendations above, but acetic acid (vinegar) is most commonly used as a herbicide. Meaning it is used primarily to KILL weeds.

You can read discussion here about vinegar and plants by the University of Maryland: https://extension.umd.edu//sites/extension.umd.edu/files/_docs/programs/ipmnet/Vinegar-AnAlternativeToGlyphosate-UMD-Smith-Fiola-and-Gill.pdf

The idea of fungicides is to kill the fungus before your plant, which is why many homebrew solutions are risky and of debatable effectiveness.

There are many proven and readily available fungicides such as garden sulphur or copper solutions that come with recommended dose rates, application methods, and warnings which should be followed for your own and plant health.

Mildew happens when it is very humid, but usually doesn't look like the little white 'dots'. Maybe it was just salts deposits, that happens quite often if watering with hard water or overfertilizing.

I water mine more often, but they are in very well draining mix. I do not use C&S soil, so can't comment from my own experience, but most ppl are saying that is not as well draining as advertised. Therefore, they recommend to add lots of coarse (sifted/rinsed) perlite or some other ingredients. "Lots of" means 50% of total volume, or even more.

Using home-made remedies could be questionable, since some of the ingredients recommended are actually not so good for plants. For example, soap or dishwashing detergent/liquid are often recommended - and not suitable to treat plants in the long run. If using soap, it should be only vegetable based.

Since everything here molds, mildews, rots or rusts you would think that I'd see a lot of powdery mildew. But I really haven't. I was thinking like Rina - it sounds like it could be mineral deposits. This jade shows some -

I, too, water my plant more deeply to help rinse any mineral deposits out of the pots. You can see how gritty my potting mix is. I have found the C&S soil to be too heavy and water retentive for my humid, wet area. I hope your plant will perk up with more water.

BTW - soap is naturally alkaline, which gives it that slippery feeling. So by definition it is non-acidic. There is probably is an acidic soap out there, but I haven't heard of it. ;-)

Thanks for the advice. I backed off on the schultz cactus fertilizer in the water when I saw the first spot. I'm just surprised the spots spread so fast. I was only using half a dropper in an 18 oz watering can. The funny thing is I've had 2 other Jade plant's and multiple cacti over 10 years and had no trouble at all with them. They have no spots.

I really don't want to overmedicate it.

Given the amount of white lumps, is it safe to spray the plant with rubbing alcohol?

My recommendation is to figure out exactly if they are scales, mealybugs, or fungus. Then you can figure out the best way to correct the issue.

Take a good close look with a magnifying glass or jewelry loupe. A good hard look and identify what's going on.

Just like a person, if you use the wrong 'medication' (poison) or even the right 'medication' in the wrong way (overdose or ineffective) you will get more sick/worse rather than better.

I agree with everything ewwmayo said. That is also a reason I described how to find out if it is scale. Scale is easy ID-ed just looking at it, but loupe or magnifying glass are great help.

If scale, spraying whole plant with rubbing alcohol should help. Just keep plant out of sunlight while treating. This would apply if using any kind of spray.

I had occasional scale on Portulacaria afra, but only on few leaves. They are quite small, and because they were just some, it was easy to treat using q-tip.