Sorry but no cigar. "Our plan" is not fundamentally any clearer in this case than "our methods", especially when the group he most recently belonged to is the Ascians, applying a very specific set of methods to restore mankind and the star, but at the 11th hour. I understand you want to believe that statement applied to the possibility of what Veloran is discussing above, where she reveals this knowledge to the ancients, and you can believe that - I certainly do not - but understand that it's not particularly convincing in cementing the notion that
any methods the ancients had available to hone dynamis, either via facilities like Ktisis Hyperboreia, or via proxy methods, or even just by sundering a select few (given that just a few sundered sufficed to dispatch Endsinger, in spite of hoarding many stars' worth of despair) would not have succeeded. That would be a rather huge stretch. Out of interest, I also checked the FR version, and I would note that his statement is broader in EN, whereas in
FR he is more specific in attributing to her (as opposed to their) methods the act of setting foot on Ultima Thule... partly accomplished, let's not forget, by tagging Meteion, as well as Sharlayan devising an escape pod. I am not sure what the JP version says, but if we say they're similar in their narrower scope, to me this undermines this as some broad sweeping statement about the ability of the ancients to devise a/any counter to Meteion had they had been told more, or even as a reference to the Ascian methods, and is just referring to getting there. A much narrower scope, I am sure you'll agree.