I'm with Lady Lee... that elder's got a lot of nerve to ask...
...but JWs tend to be nervy when it comes to asking favors. They take that "worldwide brotherhood" thing a bit far at times. They think they can ring up any old dub anywhere and ask them to do something that they wouldn't normally ask anyone else. That's how a lot of con artists work the congregations. Fake sincerity and kindness and then fleece the flock because, hey, we're all brothers and sisters, right?
Just because this is a fellow JW doesn't mean you have to put them up at someone's request. If you're feeling guilty then the WTS still has too much control on your thinking.
Since you say you've moved, this would be the time to start a progressive fade...or just drop out completely. LL has another good point: This could be a ploy to keep tabs on you, though I don't know why an elder in another congregation feels the need to worry about someone no longer associated with his congregation. But some of em are real bastards and like to play god.