You could get a feel for the setup by simply shooting a newspaper taped to a wall, at about a 1 second shutter speed, and other shorter and longer shutter speeds. That would not simulate wind that you may incur for that night shot, but would be easier than trying to find or access a similar night time scene. You would still want to do that final test...
There is a big difference between shooting a newspaper or other normal contrast scene and the night scene. With a newspaper or other normal contrast scene, you will find that exposures of 1s or more tend to "erase" mirror slap blur because most of the exposure is probably after the end of the major vibrations.
With your night scene the specular highlights of the small intense light sources will probably register very quickly so it is an exception to the general rule that extending exposures past about 1/2 second tends to actually decrease blur.
Just to say that you can learn a lot about how that head handles before doing the night test but in this case you need to test a similar night scene.
You may need Mup. Exposure delay mode may also work but this is the type of configuration where the 1s exposure delay mode may not be long enough. You may need up to 5s or so... just something you need to test carefully.