The phone ROM is with the motherboard which is what you referred to as the panel. If the motherboard is lost, he may lose all the data on the phone, but I do not know if there can be a repairer that can be able to extract the data.
I prefer to use passphrase to extend my seed phrase and I backup the seed phrase on a paper in different locations. You can laminate the seed phrase so it can be resistant to water or encrypt the seed phrase on a stainless steel or titanium steel. I prefer the normal paper because I prefer the seed phrase unnoticeable.
Same here i prefer using normal paper avoid dragging attention to it , because when we are talking about external attack even people fall under the external attack (lol) , because if you laminate am dem go wan know why the thing Dey so important and stuff .
That’s the thing so , we don’t know if any repairer can extract the data . Now he know the value of seed phrase but in a harsh way (experience) , experience will teach you but not in a friendly manner . That’s why I usually urge users to always prioritize their seed phrase .