"advised " him that he would need to inform the DWP he has this money. He said they will never find out, inferring that if they did he would know it had been me who had informed. I know this could make life difficult for me where the dc are concerned.
I might not because of this tbh, if he would know it was you..and it could cause issues.
I generally say no on these threads when its 'I know my eighbours exact income and disability status and she has a car I am jealous of and claimed benefits!!!' type of threads as its clear its full of assumptions and that and can cause a lot of issues for genuine people..BUT in this case I be;ieve you may know the exact situation.
But him knowing it was you..would probably hold me back, if its likely to cause problems.
I will say though that It also means less money in the pot for those genuine claimants who are entitled to support. is alwaysb brought up and is just such bollocks. More is lost to error than fraud, and if all fraudsters were caught, they wouldn't suddely give genuine claimants more. Of course fraud is wrong, but the 'less fr genuines' just isn't true and never will be, it should be, but its not. Same as 'people only have to jump through hoops and be told they are cured of terminal illnesses because some people commit fraud' and 'mary down the street gets pip simply for saying she has a bad back, no proof or anything!!!'. Again, it would be great if it did work that way, but the whole point of the assessments are simply to deny genuine people what they are entitled to, not weed out fraudsters, nor check accurately in any way (otherwise inches thick proof from various consultants and specialists would be fine)
But thats besides the point.
He sounds very thick, if what you have said is true about how he plans to get away with it, and he will likely be caught. Also they might already know tbh..a guy I used to work with had a 'secret' savings account and got caught by UC. Nooe could have reported him as noone even knew, so they must have just checked at some stage.
Basically, its up to you but I personally would not if it was possible it could cause problems for me. That might make me selfish, but tbh I care more about my own life/issues than about someone potentially claiming 70 quid a week for a few years before likely getting caught and having to pay it back (and yeah it will be 70 quid, if housing and such are not on, which OP says he lives rent free with his mum, etc)
I would like to say I would do 'whats best for the world' and report a guaranteed fraudster even if it caused me problems. But I wouldn't, unless I knew it would NOT come back on me tbh..