So basically, you have no evidence that ostriches existed 165 million years ago. Nevertheless, you theorize that maybe this is some heretofore unknown prehistoric ostrich variety. One that has three toes, unlike any known ostrich. And swims, unlike any known ostrich. And you're concerned that scientists are engaging in too much speculation?
Personally, I think you should go with the Lizard Men of Zeta Reticuli theory. It has about as much evidence as your ostrich theory - i.e., none at all.
We've got big bird foot prints... and we've got ostriches now. Since we get to interpret evidence.... I'd say that at some point in time ostriches lost a toe.... or that at one time there were big birds like an ostriche... only with 3 toes.
Yet you'll believe that it swims unlike any known dinosaur.