Trisiras (AKA Vishwarupa) was the three-headed son of the divine architect Tvashta (AKA Vishakarma). He was an extremely devout sage, and as I discuss in this answer he even served as temporary guru of the gods when Brihaspati had abandoned them out of anger. As I discuss in this answer, Trisiras taught Indra the famous Narayana Kavacha, a prayer to Vishnu, which allowed the gods to defeat the Asuras.
But ultimately Indra grew suspicious of Trisiras, since he was related to both the gods and the Asuras, so as I discuss in this question, Indra killed Trisiras by cutting off his three heads. This made Trisiras' father Tvashta furious, and he created the demon Vritrasura to take revenge on Indra. And it is Indra's defeat of Vritrasura that Indra most known for in ancient times.
But my question is about something related to the death of Trisiras. This chapter of the Udyoga Parva of the Mahabharata describes how after Indra killed Trisiras, Indra was not at peace, because Trisiras' body was still glowing. So he enlisted the help of a nearby wood-cutter to cut off the three heads of Trisiras:
And beholding him slain by the thunderbolt, and lying down huge as a hill, the chief of the celestials found no peace, and felt as if scorched by the effulgent appearance of the dead; for though slain, he had a blazing and effulgent appearance and looked like one alive. And, strange to say, though lifeless, his heads seemed to be alive as they were beheld lying low on the field. And exceedingly afraid of that lustre, Indra remained plunged in thought. And at that time, O great king, bearing an axe on his shoulder, a carpenter came to the forest and approached the spot where lay that being. And Indra, the lord of Sachi, who was afraid, saw the carpenter come there by chance. And the chastiser of Paka said unto him immediately, 'Do this my behest. Quickly cut off this one's heads.' The carpenter thereupon said, 'His shoulders are broad: this axe will not be able to cut them off. Nor shall I be able to do what is condemned by righteous persons.' And Indra said, 'Do not fear, quickly do what I say. At my command thy axe shall equal the thunderbolt.' The carpenter said, 'Whom am I to take thee to be who hast done this frightful deed today? This I wish to learn, tell me the exact truth.' And Indra said, 'O carpenter, I am Indra, the chief of the gods. Let this be known to thee. Do thou act just as I have told thee. Do not hesitate, O carpenter! The carpenter said, 'O Indra, how is it that thou art not ashamed of this thy inhuman act? How it is that thou hast no dread of the sin of slaying a Brahmana, after having slain this son of a saint?' Indra said, 'I shall afterwards perform some religious ceremony of a rigorous kind to purify myself from this taint. This was a powerful enemy of mine whom I have killed with my thunderbolt. Even now I am uneasy, O carpenter; I, indeed, dread him even now. Do thou quickly cut off his heads, I shall bestow my favour upon thee. In sacrifices, men will give thee the head of the sacrificial beast as thy share. This is the favour I confer on thee. Do thou quickly perform what I desire.' ...
Hearing this, the carpenter, at the request of the great Indra, immediately severed the heads of the three-headed one with his axe. And when the heads were cut off, out flew therefrom a number of birds, viz., partridges, quails and sparrows. And from the mouth wherewith he used to recite the Vedas and to drink the Soma-juice, came out partridges in quick succession. And, O king, O son of Pandu, from the mouth with which he used to look at the cardinal points as if absorbing them all, a number of quails came forth. And from that mouth of the three-headed being which used to drink wine, out flew a number of sparrows and hawks. And the heads having been cut off Indra was freed from his trepidation, and went to heaven, glad at heart. And the carpenter also went back to his house.
My question is, did Indra keep his word to the wood-cutter? Is it true that the head of every sacrificial offering is offered to this wood-cutter?
If so, is this wood-cutter famous now in Yagnas? Who is he?