UPDATE to main post. Checking all progress with the Nexus triumph, it seems that you can unlock ANY location if you eliminate the drones and activate any terminal around Europa. I my particular case, I have 1 DSC repository on Nexus (terminal) and 2 out of 3 on another augment location (well of infinitude) All DSC's need to be collected on the same location. If you switch to another location, those terminals correspond to another augment. Having this in mind, if you are on the same boat as me, we should wait for the particular scanner to the zone/location that already shows some progress on the augment AND finish ONLY the one's we're missing.. the other 2 scans should be used unblocking the right area of previous weeks.
I did 3 in the well of infinitude and i did NOT get the triumph. Apparently the Nexus is the correct location, and the only location that will give you credit for the truimph. BUT I lose my ability to complete more than a group of 3 DSCs. It sucks... means I missed a week unless i do it on my other chars. VERY expensive mistake.