I agree that this is probably the highest impact concession we could get out of Oro. But I also doubt we will get it. The man/monster cares first and foremost about time to further his own research and understanding. He would likely consider "wasting" 25-200 hours of his time/effort to be too expensive, especially if he is already close to figuring out lithosealing on his own.
We might be able to more easily secure a lesser but still viable angle of approach, perhaps something along the lines of "when we collaborate in the future, promise not to aura-blast me into oblivion if I say something stupid". It doesn't, on the face of it, cost much from him, and we can justify it as a minor line item by talking about how our idea-generation process involves a lot of "throw stuff at the wall and see what sticks" (this was even how we figured out skywalkers, it was one idea in a whole sheaf of papers we showed Kagome one day, shoutouts to the "sky pogo stick" we came up with in the same batch).
Once he's agreed to it, we now have much more leeway to raise the topics we want to discuss on our own. The promise only stretches so far, of course, but there will be some degree of Orochimaru consciously reigning back his temper because he promised to be patient with us, giving us opportunity after opportunity to say things that contradict his worldview and sow the seeds for changing his mind on things.
This works best if we pair it with some more general request to collaborate with him more, most likely on lithosealing topics as we both learn and explore the field. In all honesty, "maximize collaboration on lithosealing" was already a shortlist item for me, because even if we mutually agree to not share our
best rune ideas, the ones that we'd want to actually turn into secret weapons, I am very confident that we'd get a lot of value just by seeing what directions Orochimaru's taking his research on any given day and piggybacking off of what projects proved worthwhile or not for him
[1], to say nothing of the value we'd get from having Orochimaru of the Sannin boosting our research rolls. And as asks go, it should be relatively inexpensive, since he would naturally gain from our own expertise as well. Really, putting such an ask into our list of requests would more be described as "setting expectations and ground rules for our future collaborations" than anything else, and I think that's something we can very much achieve
and leverage to lay the foundations for changing Orochimaru's mind.
[1] One of the biggest constraints on our approach to sealing research is that we don't know what's possible or not and so the majority of our thinking is spent on adjusting and refining effects that we already know are possible. We hear of LBF and think up ARS, we add a chakra adhesion trigger to Air Domes, we take directional explosives and make rocket boots out of them, etc. If we're good at utilizing sealing effects that we know about but bad at discovering new ones, Orochimaru is the opposite: time and time again he just has the most ridiculous seal effects that we would never have tried on our own, but he never turned Air Dome upside down in all the time he had it. Just being near Orochimaru while he makes some insane rune effect we never thought of would be immensely beneficial to our own research.