So, hear me out. Necromancy.
Orochimaru has definitely heard by now of the rift, of our account of the other side, of the Akatsuki's own plans, and how he's been ordered-not-ordered to close the rift before they can retrieve Pain. He knows more than enough to hold a proper conversation with him about it without breaching OPSEC.
Our interests and his mostly align here. We both want to stop Akatsuki and we both want Jiraiya back if at all possible. Orochimaru's internal preference ordering likely shares the same broad structure as ours, "I control the rift > I close the rift > I do nothing" with the main caveat being the difference between "Hazou controls the rift" and "Orochimaru controls the rift". I'll come back to that in a second.
It would be unwise of us, I think, to share with him that we intend to go missing and steal the rift for ourselves. We don't want him to decide we will henceforth be his agent in enacting his own necromancy. But it's also true that Orochimaru is an ideal contact to have when we do go missing. He's strong enough to keep the Akatsuki from poking into his business, we can tracelessly contact him on the Seventh Path from anywhere in the world, he's an S-Rank sealmaster in a sealing race, and our interests broadly align here. Once we are already missing, Orochimaru cannot boss us around but he can cooperate with us to mutually beneficial ends.
So, if we're not sharing our plans right now but we want to build up to that end-state of cooperating with Orochimaru while we're missing, what do we do here? The main thing I want to do is sound out his perspective on things. Does he think the rift really leads to the afterlife? Is he really interested in resurrecting Jiraiya? Does he think Pain coming back is a credible threat? What would he do, in general, if he could obtain sole access to the rift? We have a pretty fair justification to be asking these questions, too. With us being forbidden from necromancy research, Orochimaru becomes our only hope for stopping Akatsuki, it's only natural that we'd be anxious to know his plans on the matter.
As for why it's beneficial to us, this is a high-stakes gambit we're planning and we need our information to be as accurate as possible. If Orochimaru isn't taking the rift seriously then that's very important to know before we bet on him being willing to cooperate with us about it. More broadly, our overall objective here is to create a scenario where Orochimaru is content helping us steal the rift, knowing that he won't have sole control of it. I estimated his preference ordering above but we need more detail, more information, if we're to align his incentives in the right way. Once we're missing we want to be able to contact Orochimaru on 7Path with a deal that goes "I will give you 90% of what you want in exchange for your help getting me 100% of what I want" and we can only do that safely once we know what that 90% of what he wants is.
This will be an important conversation in more ways than one. Not only does it scout out vital information for our necromancy plans, but raising the topic to Orochimaru also gives him opportunity to inject his own perspective on the matter. I don't think it's likely that Orochimaru would tank the brunt of Akatsuki's wrath to keep us safe so we can research without going missing, but it's not out of the question that the Snake Sannin, with his extensive knowledge and even more extensive skillset, has some advice or offer that opens up routes that seemed previously unviable. I think it's at the very least worth the low cost of dedicating some of our discussion time to the matter.
(Again, to be clear, we do not share any of our plans to go missing in this conversation. We leave off at the part where Itachi told us not to do any more necromancy research and Naruto told us to obey that order. We don't want Orochimaru deciding our plans aren't to his liking and that he'd really rather if we enacted this other plan that gives us 50% of what we want and him 100% of what he wants. We keep that card in our back pocket and focus on how our own research has been forced to an unceremonious halt, framing ourselves as a non-issue while Orochimaru remains the only person capable of making a difference, the type of story he's most likely to believe due to his massive ego).