This is because sections of the Bangladeshi diaspora in the US are of a much higher income bracket compared to those in the UK.
While Indians would anyway dominate the event, such is the strength of Indian diasporas in the UK, US or even Australia, for Pakistanis and Bangladeshis the Caribbean offers an opportunity like none other.
I doubt the validity of the above claims. Not sure what statistical basis he's using...but from what I know Bangladeshis in UK are generally doing much better than in US.
My assumption is, it's because of more Bangladeshis in US and Canada who are more cricket deprived than any other Bangladeshis.