I would have taken the residency despite what your agent says – if, as you say, there is no conflict then why not? As a new(ish) DJ, to be offered a residency would be awesome (As long as it was for your kind of music).
BUT if doing that second residency would mean that you might not be able to continue with the first then I would say pick the one that A) Will do the best for your reputation – IE Which bar is better known, which are you more likely to land more gigs from etc. or B) Will pay more (if you are bothered about that..)
However, if your agent has instead got you a gig at a smaller bar – maybe he just wanted that other gig for himself? Maybe he is jealous?
Whatever it may be, he has not acted in your best interests if you were offered a residency at a bigger bar and he instead got you one at a smaller bar which has now decided to close..
Have a check to see if they still want you at the bigger one?
Hope this helps,
bob6397