Was Amulek a polygamist? According to Alma 10:11 it seems he may have been.
The scriptures specifies Alma blessed Amulek’s “women” while he stayed at his house. The truthful answer is that we don’t know if Amulek was a polygamist or not.
The verse provides evidence to the possibility he was, however the verse provides evidence that Amulek was rich as this verse dictates, “and I have also acquired much riches by the hand of my industry.”
His implication to “women” could have meant servants who were women also in his house.
If polygamy was an aspect of his city, then the chances are higher that with his wealth he may have had more than one wife.
Thus, the answer is we do not know.