Getting taught by a God himself sounds about as ridiculous as something gets.
But once you realise who the person being taught is, it starts to make sense.
This was also the reaction of Rex and Myra. At first, they found it absurd, but the more they thought about it, the more sense it made.
And if everything William said was true, in that case, they would have no choice but to agree to let him go on this journey.
After all, they can't possibly take the opportunity of inheriting a God's legacy from their child.
And the fact that there was a possibility of finding a solution to his flaw only made this journey even more important.
That was at least what the logical side of their brain said, but it's hard for a parent to think logically when it involves the safety of their own child.
So, still unable to fully get rid of their worries, they continued questioning.