Contradiction with Exodus 25:16
Exodus 25:16 states that the testimony (tablets) should be put into the Ark, similar to Deuteronomy 10:5, so there doesn't appear to be a clear contradiction here.
Exodus 25:16: And thou shalt put into the ark the testimony which I shall give thee.
Contradiction with 1 Kings 8:9
1 Kings 8:9 says there were only the two tablets of stone in the Ark, while Deuteronomy 10:5 implies a broader context of items being placed within it, potentially creating a tension in understanding.
1 Kings 8:9: [There was] nothing in the ark save the two tables of stone, which Moses put there at Horeb, when the LORD made [a covenant] with the children of Israel, when they came out of the land of Egypt. [when the: or, where the]
Contradiction with Hebrews 9:4
Hebrews 9:4 states that the Ark contained the golden pot of manna, Aaron's rod that budded, and the tablets of the covenant, while Deuteronomy 10:5 only mentions the tablets being placed in the Ark.
Hebrews 9:4: Which had the golden censer, and the ark of the covenant overlaid round about with gold, wherein [was] the golden pot that had manna, and Aaron's rod that budded, and the tables of the covenant;