Use of the word "prove" in its various forms is problematic in debates like this. Claiming that something has been proven connotes removal of uncertainty, and this can never be the case in science. No finding in science is ever either proven or unproven. There can only be a scale of certainty or uncertainty, depending upon how you want to look at it.
Scientists use words like prove and proven all the time, but they only mean "supported by a convincing and persuasive amount of evidence," and they don't mean to imply certainty. It complicates language to stop using the word prove, and maybe a disclaimer similar to one Gould claimed for the word fact could be employed where proven would mean, "Supported by evidence to the point where it would be perverse to withhold at least provisional assent," which is what I think your position is.
But such uses of the word prove are probably best considered informal. Where precision is required, being explicit and clear about the degree of evidential support is perhaps best.
--Percy