abake
Rex Tremendae Majestatis
Yes Cameron played fast and loose with some of the lead-in continuity, particularly with regard to how the events of the first film were referenced. Obviously Kane never said that he "saw thousands of eggs there" but it was decent enough shorthand to get those unfamiliar with the original up to speed.
In my head canon there were probably some internal Company politics at play immediately after the events of the first film that prevented them from exploring LV-426 further. Heads probably rolled after the Nostromo fiasco, maybe some higher ups lost their jobs, "had accidents," etc., and those that succeeded them had pet projects on other planets that they diverted resources to or what have you.
Maybe executives above Burke's pay grade *did* have the planet surveyed and were simply playing the long game until the colonists stumbled upon the derelict themselves (so as to never leave a tell-tale paper trail like the one that Ripley discovered on Burke.) Or maybe like the Xenomorphs "not showing up on infrared" the entire Derelict ship was made out of some material that didn't show on survey scopes. It is "alien" in origin after all.
Those are some very good points...
I especially like the idea of the derelict not showing up on the scans, after all, the Nostromo crew only zero in on it because of the beacon. And the cover up after such a major disaster also sounds plausible. It would've been nice to put a line about it though... "why don't you go back and check the company records?" "we did, they were gone, a fire...".