I'm fairly certain I never marked that particular intel as important, and I imagine it would be crashing each time I opened the important tab as well if it were, which it is not and does not appear there. The only tabs which crash are the Expedition and Independent intel tabs, the latter of which I only noticed recently. I wandered over to the systems that were source and destination to take a quick peek around and found a different indie station than mentioned in the intel, presumably rebuilt at some point after the last indie port was destroyed. The destination had what I assume to be the tech cache with multiple salvage opportunities and several small remnant fleets, plus a lone indie fleet named 'Roiders' which I figured to be the tech expedition. To try a couple things out, destroying the roider fleet made no change, nor did clearing the system of other fleets and interactables.
Afterward, I poked around a bit in the campaign.xml and found what seemed to be the offending fleet. Pretty much everything in there is beyond my knowledge, but I did notice a "noAutoDespawn" set to true that seemed to be in regards that particular fleet. I've since set it to false just to see if it makes any difference down the road. Also, after a cursory inspection of the file, there DO seem to be plenty of other expeditions happening in the save, I just hadn't seen them, so that was my error. Just this one doesn't seem to want to stop giving me problems.
Regardless, thanks for the replies. I'll give it another cycle or two and see if anything changes and perhaps pop back on here if it hasn't resolved itself.