OK, I installed exTplorer, so I could put some debug code in, and confirmed my suspicion.
The problem is that you created a second Fabrik database connection, ID #2, with settings all the same as the site default, created at least one list using it (the plateforme_Situation_professionnelle one), then you trashed the connection.
So the database join for plateforme_Situation_professionnelle, which is on a form/list which is on the "real" default site connection (ID #1), sees that it is trying to join to a table on a different database (because it's connection ID #2), so it falls back to only displaying the "value", not the "label", because we don't support cross-database joins ... and fetching the label would require doing a LEFT JOIN between two different databases (well, we think it would, because the connection ID's are different).
The reason this wasn't immediately obvious is because you have uncovered what is probably a bug in Fabrik, in that we aren't checking to see if the connection a list is using has been trashed. We just look it up in the #__fabrik_connections table, and if the row for that connection ID exists, we use it. And as explained in my previous post ... when you trash something, but don't empty the trash, the "thing" (be it an element, or a form, or a connection) stays in the metadata tables, until you "empty the trash".
To fix this, I will need phpMyAdmin access, as i'll need to go and repair your metadata tables, as you can't change the connection ID for a list from the GUI.
-- hugh