I'm having trouble starting any of the included scenarios, and it mostly falls down to a couple different errors, even after redownloading and reinstalling the mod.
All versions of Eldorado 3 except for Eldorado3.biq give the following error after selecting the scenario from Civ-Content:
I did manage to get past this error with poking around the files, since I discovered that there just weren't any files in Eldorado3's tech chooser folder, so I copied them over from Eldorado 4 and got to the next error, which also happens on most of the Eldorado 4 scenarios and Solo007, though this time when launching the game after choosing any civ to play, the civ choice didn't matter:
This one I couldn't fix, since the file in question is missing from all of the Eldorado folders. The folder for I08 does exist, but there are no files in it at all. Poking around the Pediaicons.txt I figured out that it's supposed to be the Polynesian Pikeman, and trying out some of the solo scenarios showed that at least I12 (Milice15) has a similar issue, though I didn't check all the unit folders. The issue with I12 only pops up after loading up in to the scenario and opening any city-screen, so at least I get to interact with the scenario itself before it crashes.
Eldorado3.biq, however has another problem, that I'm not sure how to fix:
I'm not even sure what the error here is, I'd understand if it was missing a specific line for a unit or building, but this just seems like an empty line.
Solo001 hangs on game load, though I'm not completely sure why, and both Eldorado4b scenarios crash at scenario selection with the following error:
Copying over the relevant text from Eldorado3 just got me another error, this time with BAT038, and the text file in general seemed like it had somehow merged some buildings together, so I didn't bother diving deeper since I wasn't even sure which building BAT038 was supposed to be, where as BAT003 just seemed like it had somehow cut BAT002's main text and copied over BAT003's instead, so that was an easier fix.
In the end, I didn't manage to play any of the scenarios, even if I did manage to get them started, and most of the issues seem to stem from missing unit files, though since you've managed to get them working (at least to some extent) on your end, I imagine there was some kind of a mishap with uploading the files to Google Drive.
As a side note on the labels issue, Eldorado 3's labels seem to be from before Conquests, which explains a lot of the issues there, and Eldorado 4's labels were only missing the "Unknown" from in between "PING" and "Host" ("Organiser") on line 86.