Oh, so the author raised the issue before Trump and claims it was a popular piece. IIRC, Carson introduced his religion into the campaign by crontrastung his own deep religious experience with a, in his view, shallow observance by Trump. Therefore, by his own choice, Carson's deep commitment to SDA is on the table, so to speak.
Here’s an article on what 7As believe:
http://christinprophecy.org/articles/the-seventh-day-adventists/