No, that's a load of nonsense.
For one, the Charter doesn't apply to member states governments, only the EU and its agents exercising EU law.
The Charter is for the first time incorporated into EU law - it creates rights. If you believe this exception in the Charter can be used to reintroduce the death penalty, then by logical extension it must be able to be introduced by the EU now: a statement of rights cannot take away rights, and that is expressly stated in the Charter. The idea is, of course, ridiculous since the EU doesn't operate criminal courts.
Moreover, you only have to look at the text quoted: it doesn't allow the death penalty for rioting or anything else, it allows lethal force to be used to quell a riot or insurrection, which is surprisingly what every country in the world does. That is not a penalty.
Once again, tin foil hat, conspiracy theory bull-**** from one of TSR's resident nutters.