Overall I think Cass is better. In UK it is 5th best after Oxbridge, Imperial and LSE. Can't really say that about Fordham. If you choose Fordham, you will be facing intense competition from Columbia, NYU, Baruch, Cornell, Rutgers, Princeton, Carnegie Mellon and also numerous good colleges outside NYC such as MIT, Yale, Boston, Chicago, Georgia Tech all of which have a better reputation than Fordham. Cass is also a lot cheaper and shorter in duration. Though therefore it lacks content because you would be taking less courses than you would at Fordham. But I don't think that is your concern.
However if you have no work permit for UK, just forget studying in UK. It is incredibly hard, much harder than in NYC to find jobs in London without a work permit. A European from a far worse school can outcompete you.
As I said there are many schools which are better than Fordham but NYC job market is also much larger. You can find a full-time quantitative position in Big4 (EY, Deloitte, Pwc, KPMG). If you network well, you might find an even better job.
An alternative to Fordham could be moving to less popular areas. Chicago, despite being not large as NYC in terms of employment opportunities, is still huge. Try University of Illinois and UIUC there. You might consider Canada which is more immigrant friendly. University of Toronto is hard to get into but you might try Waterloo. Normally I would suggest University of Washington but its popularity boomed lately.
Before enrolling to a college, try to find their alumni in LinkedIn. That way you can understand whether their undergrad, their PhD, their GRE score, their work experience or their current graduate degree contributed most to their success. Each school is trying to hide their vulnerabilities. Best way to find out is analyzing background and current status of alumni and also asking them about their opinions.
Good luck
