Well, you can roll back your version of the game, and the trainer will work fine until he has time to update. I'm not exactly sure if it's possible to do it on any version of Windows before 7, but I'd be interested to know.
First, open your Origins folder, by default in your Program Files directory. Right-click the Dragon Age Inquisition folder and open Properties. Click on the Previous Versions tab, and once the list populates, select a version from before the date of the last update, then click Restore. If it doesn't let you click restore, you can still click copy, then copy that older game folder somewhere else, before overwriting your updated game folder.
Once that's all done, launch Origin first, and set it to offline mode (Origin tab/Go Offline). If you don't, then when you try to launch Dragon Age, it will force you to update. Now you should be able to use all of the features of the trainer perfectly fine. Keep in mind though, you will not be able to log in to the keep for a new game while playing, without updating your game. Also, a character created with an updated version of the game, will not work on a rolled back version. Anyway, I hope this helps you guys.