Influencers are known for promoting gambling sites, there is nothing wrong with that. It is the player's responsibility to pay attention when betting on any site. if he wins then he feels good and has a nice day. ~
No one said that what the influencers did are wrong, though. On top of that, I believe those influencers have given their own disclaimer/warning to their followers. Of course, if that guy won he wouldn't make such a fuss in the first place and keep silent with what he won.
It's tough to feel sorry for this person really because they essentially tried to take a shortcut - either he was going to lose money or someone else was going to lose money. It's his partner I feel bad for, I hope he learns a lesson but many times people will make the same mistake ~
Not too sure the reason he entered the gambling field either it's purely carried by the contents he watched or tried to take a shortcut as you said. I also hope for the same and he could earn funds from another income for his engagement.