This is definitely not allowed as it violates spiritual taboos.
Of course it can be eaten, but it is best to perform a liberation ritual first. Otherwise, the rooster’s resentful spirits and the relatives of that deity will trouble you.
The True Buddha Bodhisattva loves all sentient beings as his only son. Using the flesh and blood of sentient beings to offer to Buddha for illumination is like offering the flesh of his son to his father.
The True Buddha Bodhisattva will not accept this. The one who uses a rooster for illumination must be a fierce demon posing as a Bodhisattva. Buddhist scriptures say: If practitioners continuously kill, after death they will become rakshasas; high-level practitioners will become powerful demons...
There is also another situation: The one performing the illumination appears as a Bodhisattva, but because the common people do not understand and use the blood of living creatures as sacrifice, the true Bodhisattva will not come. Instead, malevolent demons and evil spirits will possess it to manifest.