That's a leap of logic you've made right there. Let's forget about Elliot Rodger and focus on incels as a whole. Prostitution being decriminalised gives incels a viable way to get sex. Yes sex workers are at higher risk of murder and rape, but what's the solution?
We've obviously been reading different things online. MRAs are a reaction to women having all the privilege in society and men being the disposable sex. A Voice For Men denounces incel communities/forums.