Contradiction with Exodus 20:3
This verse commands worship of no other gods, which contradicts with Daniel 3:28, as it acknowledges worship and service of another God being praised.
Exodus 20:3: Thou shalt have no other gods before me.
Contradiction with Isaiah 42:8
God declares He will not share His glory with another, yet Daniel 3:28 speaks of God honoring the protection and service to someone other than Him.
Isaiah 42:8: I [am] the LORD: that [is] my name: and my glory will I not give to another, neither my praise to graven images.
Contradiction with Deuteronomy 6:13-14
These verses instruct to fear and serve only the LORD, while Daniel 3:28 praises those who served their own God instead of the king's command.
Deuteronomy 6:13-14: Thou shalt fear the LORD thy God, and serve him, and shalt swear by his name.
Contradiction with Jeremiah 25:6
Warns against following other gods, contrasting with Daniel 3:28's approval of serving another god.
Jeremiah 25:6: And go not after other gods to serve them, and to worship them, and provoke me not to anger with the works of your hands; and I will do you no hurt.