Xuanchenzi spoke of a fusion with the Primordial Spirit that was identical to what Buddha did for Vijadara; it could be said that neither the Taoist Ancestor nor Buddha would choose the crude method of forceful spirit possession employed by the Great Celestial Demon Lord, as it's too rough.
If it is as Xuanchenzi says, then sooner or later, Lin Changhe's memories will be devoured by the memories of the Taoist Ancestor. In that case, the Taoist Ancestor will still be resurrected; it is just a matter of time.
Xuanchenzi said solemnly: "This method is akin to quenching thirst with poison. The only way out is one thing – you must advance to the Sky-Reaching Realm before the memories of the Taoist Ancestor completely merge with your own!