Perhaps you could put a box of your trench frames on top (in the middle, or somewhere) of your hive as to get the girls to start working those frames.
See, the #1 problem I see is not getting the bees in the trench hive, but how to keep them there, with food stores, brood, pollen, etc. I wouldn't want my girls to just start from scratch, and have a new hive the queen wasn't interested in making her home.
So I thought that if you have trench frames that have already been somewhat worked by the hive, they have a familiar smell, and of course, are the correct size. Then you move those frames first, and then shake the bees in. They'll feel right at home.
If the majority go by shaking, then the rest will follow. So put a sheet in front of your trench hive and make a path for what fall in front of the hive can walk/fly themselves in.
Know what I mean?
Here's a swarm marching/fanning/scenting the air while entering their new hive. It was a cute little trail of bees from the small tree they took refuge to, to the Nuc I shook them into as a temp. home: