Look at the reality of the situation;
On the one hand - you have the Russian government, who are world class pros at deleting people who've upset them, from spies to political opponents - it's a matter of fact that Russia has been knocking them off, it's something they're well known for.
On the other hand - Here in the UK we have a political establishment, that is absolutely falling to bits, ridden with utter incompetence. Comprised of individuals that more closely resemble cattle in a field than human beings, all totally consumed by the Brexit project. Unable to operate with any coherence, unable to march in step, unable to deliver anything of value for anyone.
In my opinion, it's literally almost impossible, for our government to pull off a conspiracy theory like this, they simply don't have the power to do it, these people could **** up a cup of coffee, never mind orchestrate a conspiracy theory as difficult as this.
This is all the work of Russia, with no other serious competing theory - it can't really be anyone else, it has all the hallmarks, they also have the motive - when you look the evidence it is the most likely and reasonable explanation.
It's also entirely possible in my view, that this could be an attempt at plausible deniability. It could also be an attempt to disrupt our participation in the world cup, by causing enough disruption and upset to throw our system into chaos and possibly hurt our chances.