it is somewhat dated;
plus, I have read the first edition, the approach didn't really change by a bit;
you take the vuln, describe the idea and presents your reader with a report on hackerone;
I mean, it is probably what you are paying for but it is way too oversimplified + it is depicting some rare and useless vulns which are hard to spot in the wild.
Still, as a basic intro to bug bounties this might be a good reference.