Many happy, well grown orchids release this "honey dew" to attract ants and bugs for pollenation. It's a sweet, sugary, sticky residue. I get it in my hair all the time and it's a real PITA. I've got long hair and have to make sure it's put up before watering or I'll be sorry. I mainly see it on my dendrobiums, phals and some oncidium types and some others. Phrags and paphs don't get this so if you're seeing a sticky substance on them, there's a problem.
Then what you've got isn't honeydew but scale excretion-yuck. Neem won't do much for you I'm afraid. If you grow indoors there are a few less toxic options available. I'm sure an indoor grower would love to give you some hints. I tend to fire the big guns-pesticides when I see scale in my g.h.