Alliance

Flashes of information Cain and Amber already know swirled through their minds. 

Because of Zi Yan, the duo had knowledge of both Wen Shao and that 5 Divine King inheritance that Jiang Ling didn't directly mention. 

Both of which are legitimate reasons on why he would stay completely locked within his chambers. Stepping out was the equivalent of risking his life as he's potentially missing out on a valuable breakthrough. 

Cain just wanted to hear it from Jiang Ling's mouth and analyze his sincerity. 

With all of his actions up until now, Cain could safely say that Jiang Ling is genuine in all of his eagerness. 

Still, it was only natural that neither Cain nor Amber could ever trust Jiang Ling or Wen Dao, at least in the short term.

If the other party is weak, then it becomes highly possible for them to get overly oppressed without any chance of fighting back. Whatever the weak get, would simply be coveted by the higher-ups.