Yes. That is exactly right.
A tihetuka person WILL NOT be born without sota pasada rupa.
– But their eardrum or some other part of the brain may be damaged, and they may lose hearing.
– If they can repair that damage or use a hearing aid, they may be able to hear.
The following account is from the post “Gandhabba in a Human Body – an Analogy”
Sometimes people are born with the cakkhu pasāda rūpa in good condition, but the optic nerve (or the physical eye itself) may be damaged. In that case, they cannot see because the brain is not getting a signal from the eyes.
But if the gandhabba can come out of the body, it can see by itself. The following video clearly illustrates this situation.
Note that she had “never seen anything” in her whole life. It seems that either her physical eyes or the optic nerve/visual cortex in the brain had been damaged at birth. But the cakkhu pasāda rūpa was fully functional. That is why she was able to see when the gandhabba came out of her body.
– However, in other cases, one may be born blind because one may not be born with the cakkhu pasāda rūpa. In that case, even if the gandhabba comes out of the body, it would not be able to see.