Dominion does not include the menu
Verse 28 gives humans authority over every living creature. Verse 29 lists what they are to eat -- and not one living creature appears on that list. The grant of dominion and the grant of food are deliberately kept separate.
A landlord may own every room in a building and still not have the right to take whatever is inside them. Ownership of space is one thing; entitlement to contents is another. The two do not automatically follow from each other.
The sequence here works the same way. Verse 28 is expansive: fish, birds, every living thing that moves. The scope of human authority is total. Then verse 29 opens with "Behold, I have given you" -- and the gift is seeds and fruit. Every herb, every tree. The list is careful and complete, and it contains no creature.
The animals just placed under human dominion are not placed on the human table. The verse does not explain the gap. It simply draws it. 'Your food' is defined, and the definition stops at the plant kingdom, even though the previous verse had just handed humans the animal kingdom entire.