The answer
After several spent time we were able to recreate the database doing the following:
1.- Remove the RDS role
2.- Delete or rename the folder C:\Windows\System32\LServer (this is where the database file lives)
3.- Install the RDS role - the LServer folder will be created from the scratch so no license will be there
Extra
4.- Just in case, enable the feature RD Connection Broker if the server is intended for supporting several connections
I hope this helps anyone out there