Although Yusuf Zuck lost his memory and doesn't know who he is, he still retains the vigilance, caution, and cunning he should have. He is not an idiot; it's just that he lacks the memories of the first half of his life.
Therefore, when Hector Dyer proposed that his family's patriarch help Yusuf enter the Immortal Transformation Pool, Yusuf voiced his concerns.
After all, Hector was still a child, a teenager. Perhaps his mind matured quicker due to living in such a big clan, making him more sophisticated than the average adult. However, he wasn't the decision-maker in the clan, meaning his words did not carry weight.
So if that Dyer Family patriarch, Raymond Dyer, found out about Yusuf, an outsider or a mere mortal, practicing their family's secret technique, what would he think?
"This should be fine, right?" Hector thought for a moment and said, "Grandfather really loves me!"
"He loves you, but I'm afraid he won't love me, will he?" Yusuf smiled bitterly.