You may be losing roots from spraying alcohol.
At least in my experience when I've accidentally sprayed alcohol on the roots (by trying to spray the leaves, never purposely in the media), the roots have become scarred. They still function; I sprayed them with water right after I got alcohol on them... They're still scarred on the outermost layer though.
May I ask how you've prepared the bark when repotting? Did you soak it, how long? Some barks have "junk" on them that is removed by soaking them overnight. I usually change out the water at least once.
* The bark you can get at the box store should be soaked and rinsed really well. I've found that mine personally has a lot of salts (box store bark.)
I definitely think the plant is stressed from being sprayed with alcohol, and from being repotted. I learned to be careful with the alcohol as it can also further damage the plant. When used carefully, it's okay though. If you need to use alcohol on the leaves, maybe try a cotton bud, q-tip, or a little paper towel dipped into alcohol. This way avoiding the roots will be easier.
If the white deposits disappear when you water the phal, it could be build up from the new media.
I don't know if you would like to, but a TDS meter can be handy. You can test the water you're using to see if you're using hard water. Also you can check to see how the TDS changes when you soak the media. If you can, try to pick one that has temperature compensation. I use amazon, so I'll add a link to the one that I use. It's reassuring to know the TDS of the water I use for my plants; I would recommend getting one if you plan to grow several orchids.
When I bought this, it said it had ATC(auto temp compensation). It's still fairly accurate with temp changes but it's not the best meter. HM Digital TDS-4 Pocket Size TDS Meter 0-9990 ppm Measurement Range , 1 ppm Resolution, +/- 2% Readout Accuracy
https://www.amazon.com/dp/B0002T6L5M..._UDm8ub0NCFP6M