Abinadi is pretty clear that he understands that his mortal frame will not survive this encounter with Noah. It is possible that there were options open, for if all had repented as did Alma, then the result could have been the freeing of Abinadi, and perhaps the destruction of Noah's regime might have been avoided. Clearly, however, Noah and most of his priests not only did not repent, but they gave no credence to his words, for they chose to burn him, even though he prophesied (correctly) that such would also be the fate of Noah.
The account of Abinadi before Noah appears to have a foregone conclusion from its beginning. However, even though the probable outcome of the encounter was known, probably even to Abinadi, yet the Lord left room for repentance.