Well one thing you must understand about Europe is that their ruling class only cares about profit and the ruled class is very subservient to whatever the ruling class tells them. In the event that the European ruling class's investments in America get fucked, there is a possibility of Russia opening investments for Europeans, which will immediately cause the European policy to revert.

Of course that would be a reversal of a decades long relationship of capital between the US and Europe, however, these are exactly the times where such decades long trends are being broken. Not to mention, as the US declines and a crisis of overproduction builds (AI), it is only a matter of time for investments in the US to be tanked.

The real factor is whether or not the Russians are willing to play ball and treat the euros with kiddie gloves. I'm sure they'll extract some juicy concessions if they are. But fear not, the euros are experienced with servicing greater powers.