There’s more than enough information available and there’s always the trial and error method where you learn from your mistakes. Guides only really serve those who don’t want to put in the time and/or effort to do it that way.
As had been stated in the thread, you can simply sign up for the trial, which is free, in order to get those rewards. So yes, it’s possible to get them for free.
It’s been a common issue where people who get downed don’t get credit. It’s been six years so it could have been among one of the dozen or so bugs they have fixed since that time.
If you’re not in a rush, and you intend to do the achievements for each episode of LS4 for the highlight weeks, I suggest just waiting. You’ll get more than enough currency for something you were going to do anyway.