JAD2012: That's hilarious, because what made me make this post is guides/wiki claiming behind that door there's a legendary crafting blueprint XD
Now I wonder if official guide content is based solely on gameplay plans too and not actually playing the game...
I remember. I read the same thing online, as I was in the same position back then. I also searched high and low in the Bender Blender for the access shard, but I never found anything. I also remember falling through the map when i tried turning the ghost hack off inside the room.
But for all I know, it might be fixed now, and that the card is hidden somewhere (I do doubt it though) - I did the mission awhile back, but didn't bother looking for the shard one more time (was tryng to be sneaky about the gig ^^), and didn't revisit it after.
I can give it another go. Ghost hack doesn't work anymore though, so the door is truly locked if there is no access card. Seriously though, a simple blueprint is not worth that much hassle - if it's even in there now, it's just a print for the Legendary baseball bat or a mod or something.
There was another such issue elsewhere. A hotel gig, nearest Fast Travel point was El Coyote Cojo. If you're discovered during the mission, you'll get a shard to take the elevator to the basement to escape. And down there is a box with some Legendary components in it.
Which was only possible to get with a ghost hack, as the box was fended off and with no access door. You could only see the Orange icon, indicating something legendary. I did that mission without being discovered this time, so I didn't get the access shard, so unknown whether they've fixed it.