unable to delve at all in 3.26 - bugged on 2 characters

hi GGG folks,

I started late in the league and have a RF Chieftan at level 85 ...

I have noticed since Act 4 I have completed "Niko's Fuel" but still have the quest "Niko's Mine" outstanding.

When I go to my Mine Encampment to try to complete it, i notice the Voltaxic Generator is missing.

I can click into the Azurite Mine and talk to Niko ok once there but when i click the crawler to get it moving my Subteranean Chart is empty, just a black page with no path at all.

I thought maybe it was just this character that was bugged so i levelled a second one to Act4 and it has the same problem.

Any help would be greatly appreciated.

forgot to mention i'm on Mac and i saw in known bugs from last year there was something abut Mac and Delve. Is this still a thing? How can i get details?