I am not offering a counterargument and definitely not an inadequate one.
Then you fail to have demonstrated that my argument is in any way inadequate.
Because logically the opposite of determinism is non determinism. He seems to have jumped a step to introduce randomness
while not showing his warrant to discount other things which are non deterministic.
Such as what? Given a state of your mind (or anything else, for that matter) and its environment at some point in time, either there is only one possible future or not. If not, there can be no possible
reason for the different possibilities (because the starting point is identical for all of them), so there must be something that happens for no reason and hence it is random.
Or, if you prefer, you can imagine rewinding time and running things again. Either the outcome
must be the same or not, and if not, that again means that means that something changed for no reason.
It dismisses also the human response to God where there is nothing in the universe that is like God...
Yes there is, all the other baseless superstitions in the world (including all the other gods that don't match whatever you mean by 'God').