Student or Learner
Is it true that the usage of Appostrophies is not encouraged in US Business English?
No, that's not true at all.
If you mean that we don't use a lot of contractions in formal writing (isn't, didn't, don't), that has a small amount of truth.
I am a business writer and I make my living writing business English, and I use contractions when they sound natural. I omit them only in the most formal types of writing. In articles, brochures, presentations, and of course e-mail, I use them.
(Note the correct spelling.)
I'm not a teacher, but I write for a living. Please don't ask me about 2nd conditionals, but I'm a safe bet for what reads well in (American) English.