The water explanation certainly comports more with the biblical account of how things were before the (re)creation (Genesis 1:2).
It does. Neato.
If this had anything to do with the flood, I wonder why Noah didn’t have any dinosaurs on board?
Only if you accept that Noah deliberately ignored God's instructions by not putting any of them into the Ark.
"And of every living thing of all flesh, two of every sort shalt thou bring into the ark, to keep them alive with thee; they shall be male and female.
Of fowls after their kind, and of cattle after their kind, of every creeping thing of the earth after his kind, two of every sort shall come unto thee, to keep them alive." - Genesis 6:19-20
The Bible accounts for more than one flood covering the earth. Consider rather the biblical account of the earth covered with water before the (re)creation (Genesis 1:2).
It is a little simpler than the bible. It’s not that all dinosaurs drowned. It’s that the fossilized Dino’s died near/in water and the sediment eventually covered them, and thus they became fossilized.