Only through Liu Wuxiang and the influence of the entire Liu Family could your control over Supreme Changrong Heaven reach its peak. This could be considered an alternative way of "holding one person and one power hostage to command heaven and earth"...
To accomplish this, either your strength had to rise faster than Liu Wuxiang's, or he had to be given no time to improve his strength. You intended to do both. Rather than rushing to Supreme Changrong Heaven to carry out the plan, you would digest your recent gains while finding something for Liu Wuxiang to do, leaving him no time to continue his secluded cultivation and increase his strength.
Entrusting such a heavy responsibility to Liu Xinxian alone was certainly not enough, so you had already planned a move to "drive the tiger to devour the wolf," sending the Void Spirit to cause some trouble for Supreme Changrong Heaven.
Naturally, this carried a certain degree of risk. The Emperor Corpse of the True Tribulation Underworld Lord, having fully regained its vitality, was not weak. Even with World Protection, Liu Wuxiang could not claim with certainty that he could withstand it.
But then again, if the situation were not grave enough, it would be impossible to force Liu Wuxiang, who had already entered a crucial period of secluded cultivation, to emerge early.
Moreover, this was not entirely without a backup plan. So long as Liu Xinxian remained as your eyes and ears, coupled with the special nature of Supreme Changrong Heaven, if matters truly grew too big to control, you believed the Dao Sect would not stand idly by. Once the Dao Sect's experts intervened, the Void Spirit would surely have to avoid their edge.
As for whether Liu Wuxiang might report the matter to the Dao Sect before