Start with the hard case: humans make choices which are free and accountable. Yet there are plentiful biblical accounts that God is, in a mysterious way, sovereign even over such choices, without compromising their freedom. That is old theological news, discussed and disputed since before Christ - and the best accounts manage to hold the will of God and the wills of humans in tension. The reason that is done is because both are free, conscious agents.
None of that is relevant to nature, except inasmuch as animals make some kind of choices analogous to ours, yet to lesser degree. Neither human nor animal wills are anything to do with randomness, but to do with greater or lesser degrees of deliberate choice (and lawlike activity).
That leaves the non-sentient processes of nature, including physics, chemistry and biochemical processes encompassing, on current theory, evolution. This is where the question of ontological randomness hits, but where is it to be found?.
Yes I do have such grounds, which I’ve laid out extensively in the past, on scientific, philosophical, statitstical and theological grounds.
Scientifically, at the macro scale, I know of no evidence for ontological chance that is not equally explained by lack of data and/or divine choice, and in fact we can see from simple cases like the coin toss that probabilities arise from determined, but humanly incalculable, causes: coin tosses are not determined by probabilities, but the mechanics of the coin toss produce a statitsical pattern which allows prediction, This appears to be true of every “random” phenomenon of this type.
Even at the quantum scale, it is not clear that the same isn’t true, once one escapes the need for local variables to produce outcomes: see my latest post on Heisenberg for this (as soon as I can get round to posting it…)
Statistically this may be explored further, as William Briggs does in his book Uncertainty. Philosophically, the idea of causes arising undirected is problematic - and in fact the world does not exhibit unordered causes even in its probabilities, but patterned events.
Theologically, I critique ontological randomness in the context of Molinism in my recent post. No definition of “random” can exist with the classical Christian concept of God: he knows all things, so “of unknown cause” does not apply to anythying whatsoever from his viewpoint, and he is the Creator and cause of all things, and so “of unknown cause” is equally absurd. If one reverts to concepts like “without cause”, then there would exist a force of chaos existing eternally alongside God to make the universe, in part, unintelligible even to him. Or else God creates causes that he doesn’t cause… Duh?
Molinism works as badly for chance as it does for free will, with the difference that we at least have good reason to believe that free will exists, and no good reason to believe that ontological chance exists.
Footnote: to Aquinas, “chance” consisted mainly of the accidental “collision” of secondary causes. Local example: my swallows built a new nest according to their inborn skills and the principles of physics. I found the nest had fallen on Wednesday owing to the force of gravity and the non-adhesion of their mud. Yet no ontological randomness is involved - and theologically, Jesus says in reassuring individual believers about God’s care that even the sparrow does not fall apart from God’s will. Presumably swallows are no less privileged. And hence Aquinas strongly asserts that chance, as well as everything else whatosever, is governed by God’s providence.
If that is not so, and ontological chance is said to exist, created by God, what purpose is served, other than to make God’s providential care impossible? Chance damages my determinative will as much as it does God’s, and renders the whole universe in a degree of slavery to irrationality.
Edit: New post is