Now, what you may need to do is come up with a "reason" to have convoy vessels close enough to make a diorama of.
1000 yard seperation between convoy vessels is pretty tight navigating quarters; escorts are likely to not be closer than 5000 yards without some good reason.
Now, a Liberty with a boat in the water investigating some flotsam or wreckage with a DE nearby might make sense. An empty lifeboat could add poingnacy, as would flotsam with a smudge (black-sprayed cotton wadding) of smoke drifting off.
Nice touch to that is that the DE can have weapons trained all over the place, alert for all of the dangers that could be out there. Downside is that this really wants dozens of figures, which could be a lot of painting & bending in 1/350 (not that 1/700 would be that much simpler <sigh>).
Alternate situation might be if some one were being high lined in a bosun's chair from the Liberty over to the DE (with the attendant need for lots of teeny-tiny detailing).
Now, a person could take a "British" tack to this and cobble up on of the stop-gap cat-launched Hurricane cargo ships, where the pilot had to ditch afterwards, and the DE & cargo ship could be in close (2-300yd) proximity for that evolution.