have pictures of the gaskets you have?

Your core looks like a WBS stage 2 without front PCV to me.

But I can't be 100% sure.

Did you get a LIM from them as well? If so, have pictures of that as well?

Edit: At second glance it looks like it has front PCV as well, thus ZZP core, but again, depends on the LIM.

You could use RTV (doesnt matter what kind) but make sure the front PCV isn't filled with RTV, but still sealed.