You should know that there are a total of eighteen Cloud Giant leaders, and only with some of the leaders colluding could it be possible to blindside Muria's surveillance. It was definitely more than just two Cloud Giant leaders.
Thus, once he had determined which Cloud Giant leaders had attempted, through various means, to prevent Muria from accepting new Giant allegiances, he didn't hesitate to exile them; yet, Muria still harbored kind intentions, granting these eight Cloud Giant leaders a chance to redeem themselves.
During the six months since Muria had arrived at Taiji Island, his consecutive banishments of Cloud Giant leaders had truly terrified most Cloud Giants, leaving them in a constant state of unease. Under this atmosphere of fear and anxiety, construction of the Giant City, which Muria had not specified a completion date for, was progressing at a rate that astonished him.