Sui Xiong was naturally unwilling to let go of a disciple. This was especially so seeing as Kalisa belonged to his church's inner circle. This was not just a problem of benefits but also an issue of personal relations.
If Kalisa had followed the Goddess of Love from the start or if the Goddess of Love had approached him thirty, forty years ago to discuss this proposition, he would have agreed without much thought. However, Kalisa had already been an important member of the Void Mask Church for the past fifty years and was heavily involved in the core of the work, gaining her respect and trust among the followers. She had already become indispensable and irreplaceable. Thus, he would definitely not accede to her request now.
Furthermore, he had developed such a longstanding relationship with Kalisa; surely he could not be expected to just give that up overnight!