No. Doing normal business using the AH is 100% fine. Posting items in the realm of their realistic gold value is fine.
What is not fine is listing vendor/low quality junk for large amounts and having that mysteriously bought. Posting pets or transmog for their actual value to avoid suspicion then maybe having those items returned to you, or relisted cheap so you can buy them back quickly.
Blizzard isn’t dumb, no matter what some people think. It’s not hard to tell who is just doing normal business and who is laundering. No, they will never tell you how they catch someone doing it. And no, the people caught will almost never admit, they will just continue to play dumb.