That's not much more than Putin taking advantage of the focus on ISIS and Islamic terrorism. The relationship of Russia and Islam is variable, they fight some and support others. Not much different than other countries like the US.
The difference is that the neo-sovs indeed consider Eastern Europe to be nations without rights, that need to be re-conquered at first opportunity. Militant Islam rising in West Europe will give Putin such opportunity.
There is another factor. Muslims in Western Europe are concerned, very often, with things we Christian conservatives are concerned about: establishment of pro-gay and anti-religious regimes all across Europe and the US. Putin might see an opportunity also to build a fifth column of supporters in the West, if the cultural left wing solidifies against the Muslims.