China is after Pakistan and Pakistan is after USA. Given the foreign policy invested in western worlds, that is why Pakistan establishment have hard time separating from USA. But in WW3, it will be survival that will decide the side - not for monetary reasons.
If Pakistan, China, Russia, and possibly North Korea along with Iran join together, it will be for survival - not for monetary reasons. WW3 is matter of survival and that is why they maintain the relationships purely for that reason alone.
At the end, the survival trumps the money card so Pakistan is being smart to keep all the options open just in case. I expect every nations do the same for the survival.