The rar file is fine and includes the trainer exe and the readme as intended.
Please check your antivirus logs. Depending on your AV the extraction process could be interrupted if it scans archive files.
Please uncheck this option in your AV or move the rar file into a folder which is already excluded/whitelisted in your AV and extract the trainer.
I just checked our latest trainer on the game also with all DLCs installed and everything is working as intended. Did you exclude the trainer in your antivirus/other security software and ran it with admin rights?