When Mormon abridges 4th Nephi, this is when the events really occur and he writes of them again. So here's another example of internal consistency.19 And they were cast into prison by them who did not belong to the church. And the prisons could not hold them, for they were rent in twain.20 And they were cast down into the earth; but they did smite the earth with the word of God, insomuch that by his power they were delivered out of the depths of the earth; and therefore they could not dig pits sufficient to hold them.21 And thrice they were cast into a furnace and received no harm.22 And twice were they cast into a den of wild beasts; and behold they did play with the beasts as a child with a suckling lamb, and received no harm.
30 Therefore they did exercise power and authority over the disciples of Jesus who did tarry with them, and they did cast them into prison; but by the power of the word of God, which was in them, the prisons were rent in twain, and they went forth doing mighty miracles among them.
32 And they did cast them into furnaces of fire, and they came forth receiving no harm.
33 And they also cast them into dens of wild beasts, and they did play with the wild beasts even as a child with a lamb; and they did come forth from among them, receiving no harm.
Another observation I made is the examples Moroni is using when finishing his father's record and describing men of faith in Mormon 8:24
And he knoweth their faith, for in his name could they remove mountains; and in his name could they cause the earth to shake; and by the power of his word did they cause prisons to tumble to the earth; yea, even the fiery furnace could not harm them, neither wild beasts nor poisonous serpents, because of the power of his word.Obviously, Moroni has been reading the plates and taken note of the three Nephites and the description his father gave.