Sounds like poisoning. But I could be wrong. Birds are so hard to diagnose without great potential of error, so many of their symptoms are alike or identical for so many different problems... Activated charcoal is a good first stop, even for viruses, and over-proliferation of bad bacteria. The trance like staring is usually associated with toxicity, but so is twitchiness. Or it can be. Depends on the level of damage. If you have pets, kids, livestock, even if you only have yourself to look after, activated carbon/charcoal is a great first stop for accidental poisoning, contaminations, a whole bunch of nasty problems. It's a lifesaver.
So is raw unhomogenised and unpasteurized milk, raw honey, rescue remedy, and 'zappings' --- an old bushie method of counteracting snake venom when you're out in the 'Woop-woops' and get bitten and have no help nor any way of getting to a doctor in time. You need a car that's pre-1980s though. You start it running, idling, take off a sparkplug, put a conductive wire in the socket, attach it to the ground (easier if you wrap it around a screwdriver and jam it in the earth, and easier if the earth's wet) and now that it's earthed, you put both hands at once on the bumper or any exposed conductive metal. Both at once because that won't hurt, whereas all the voltage going through one finger will. It's saved many lives, animal and human, from fixing toxic shock syndrome to viruses to snakebite and random poisonings and infections of all sorts. Bizarre, I know, but remember it, if you're ever dying and unable to get to the doc's in time.... I've used smaller commercial zapping units on poisoned chickens with success. Kinda like those units they use to strengthen racehorse tendons. Best wishes with your rooster.
Hens go broody when you don’t want them to… and won’t go broody when you do. 
