As you have found, most IP67 connectors are not IDC. Two big names I can suggest you look at are Bulgin and Binder. They have a wide variety of IP67 rated connectors with varying styles.
If IP67 is a must, you are probably not going to get an IDC style connector, simply because to get that rating, there has to be a compression seal all the way around the connector, and IDC connectors only have fit compression at the ends, not all the way around.
You can get IDC (for D style connectors, for instance) if you can live with IP44 or thereabouts, but I don't recall seeing anything above that.
I (occasionally) design IP67 stuff, and connectors are always my single biggest concern (to say nothing of cost).