It certainly would have been interesting if Terri's parents had taken custody and then she choked to death because they were trying to feed her. They did insist she could swallow, so it is quite possible that might have happened.
Don't be ridiculous. That isn't even the point; their desire to care for her rather than kill her off is. But if "their manner of care" were - what makes you think they'd always be insisting on stuffing things down her throat thru her mouth?