Tales From The Eridian Slab (How to get the achievement?)

Did you find all the letters, but still haven't received the coveted achievement? You're at the right place!
(The description of the method comes from how my friend AZ and I received this achievement on the PC version BL3)
At the time of receipt, AZ and I had already replayed the game on TVHM, had 72 levels, all, except the cherished, achievements and 30/30 Eridian slabs.

Step 1
Look at the map and press the "X" key until you exit to the planet selection menu, then press the "R" key and look at the number of Eridian slabs. If the letters are not 30/30, then by the same method we search on which planet, and then in which place you did not activate the Eridian plate(s).
https://steamcommunity.com/sharedfiles/filedetails/?id=2715462486

Step 2
Return to the Sanctuary and check if you can reuse the stone slab near Tannis.
If after reading you did not receive the achievement, then try to re-enter a couple of times and try to read it again.
If you still haven't received the coveted achievement, then proceed to the next step.
https://steamcommunity.com/sharedfiles/filedetails/?id=2715450089

Step 3
Create a new character (if you have any DLC, then create it immediately with a pass for LVL 13). Then go through the main plot of BL3 up to the "Space-Laser Tag" mission, go to Meridian, but do not do the mission. Not far from us is the slab we need. Restart the game completely. Invite a friend (or log in from another account) who has an artifact for reading Eridian slabs to the lobby. Ask a friend to use the Eridian slab and get the cherished achievement! (If you played the game with a friend and he, having an artifact, cannot use the Eridian plates, then just completely re-enter the game and invite your friend again).
https://steamcommunity.com/sharedfiles/filedetails/?id=2715451707
https://steamcommunity.com/sharedfiles/filedetails/?id=2715452400
https://steamcommunity.com/sharedfiles/filedetails/?id=2715453214

I hope this method helped you and you got the coveted achievement ^_^

Explanation of principle and notes:
1) In fact, the method works in all places where the respawn point is close enough to a particular Eridian plate (that is, the method does not depend on the main or side quest, except the quest with the selection of an artifact that allows you to read the slabs): at least in the same Meridian with an earlier task "Hostile Takeover" or when restarting before the battle with Trant on Athena - there is no difference.
2) The method does not work on "old" (which have all 30/30 slabs) characters, only on new ones!
3) Achievement is received only by a new character, the one which helps us - not (perhaps the method works for those who did not collect all the slabs, I did not check)!
4) Perhaps a simple reconnection is enough, and not a complete restart of the game (did not check, restarted the game completely).
5) Most likely, the method is universal for platforms, since it uses the mechanics of the game itself (I have not tested it on PS).

[xxxymoxxx]

it's much easier than this. Make a lvl 72 characters, go the opposite direction of the vending machines, tap the eridium sign, boom

[HezaK]

the game glitched out and i unlocked this achievement after scanning my first slab.

[Tai]

Lucky)
Yes, this is not rare, but more often it happens that a person goes through the whole game but cannot get this achievement on his favorite character.

[Clover]

okay so SOME HOW i got this achievement on the first slab i deciphered (besides the tannis one), the one near the nekrotafeyo vault key. idk how exactly this happened though...