It doesn't make sense that people will migrate from England to Crimea just out of the blue.
It's only make sense if they were already in the Mediterranean region and then were looking to settle in either colder climate, free rich lands, or a combination of the above.
There are also older anti-Normanist theories that Kievan Rus was founded by the people/warriors from the South (i.e. Crimea or adjacent Sea of Azov area).
[1] https://en.wikipedia.org/wiki/Crimean_Goths