Formal fallacy, affirming the consequent
That wasn't a fallacy, he wasn't implying that the latter logically followed from the former. It was just a statement.
It was a fallacy because it assumes that DA1=DA2 which is not true.
No, he used the term likely.
Likely still assumes similitude which DA2 has none to DA1 and that is the reason which has alienated most of us away from it.
There was no logical fallacy in his post. It may have been incorrect (really, none of us are in the position to judge at the moment), but there was no fallacy.
If P, then Q
P, therefore Q
That's a fallacy because his statement is not true.