This seems really weird and I'm not sure what's causing the error to occur. I tried recreating the issue but I was able to publish successfully to Tableau Server when I had Tableau Desktop set to Spanish.
I recommend opening a case with Technical Support and providing the following information:
1. How you're configuring Tableau Desktop in Spanish (I.E, are you setting the workbook locale or changing the language under the Help tab).
2. Is Tableau Server configured to run in Spanish or English?
3. A clean set of Tableau Desktop logs creating the problem. Instructions for gathering clean logs can be found here: Sending Tableau Desktop Log Files | Tableau Software
Your issue seems relative to the very annoying issue I faced last days. Let me share what I understood and the "workaround" :
If I create and save a workbook in a specific language (ex French, selected from Help pane) and want to open it in an another language (ex English, selected from Help pane), I won't be able to get my data source back.
At the moment I want display the DataSource, I have a message (Errors occured while reloading the data source / Warning: Local folder 'Mesures source' discarded due to conflicts with remote folders.) :
Then the DataSource is broken as all the workbook, all worksheet fields are in red.
The get the workbook working back, I restart Tableau with the same language than the workbook and open it. This way everything works again.
I use Tableau Public 10.5.1
Hope it will help.