Just for reference, the screw worm is a fly that lays its eggs near the edge of an open wound. The eggs hatch and do indeed consume the surrounding flesh. Some species will only consume dead flesh and have been used to clean up wounds in third world contries.
I suppose a fly could have laid eggs in the rice and beans but I am not sure if the eggs or hatched larvae could survive in the digestive tract.
As far as the “worms” laying eggs in the digestive tract, doesn’t happen. It is the fly that lays the eggs.
https://en.wikipedia.org/wiki/Cochliomyia
It looks like you did more research than she did. But then there is
"Flesh-Eating Worms Invade Woman's Ear." The scratching sound that Rochelle Harris kept hearing was all in her head — literally.
After the British tourist returned from a vacation in Peru earlier this year, she started experiencing headaches, shooting pains down the side of her face and an unexplained discharge from one ear.
Those symptoms, plus the bizarre scratching sounds she continued hearing, prompted Harris to visit a doctor soon after her return to England.
Though doctors at first dismissed the symptoms as nothing more than an ear infection, specialists soon made a startling discovery: Harris' ear was filled with flesh-eating worms, according to the Daily Mail. The worms that Harris, 27, was hosting were the larvae of the New World screwworm fly (Cochliomyia hominivorax). http://www.livescience.com/38204-flesh-eating-worms-maggot-therapy-screwworm-fly.html