Unfortunately, this is at least partly a problem on the Kobo side. When the device sees a sideloaded book, it process the book, extracts metadata and puts it into an internal database. That is used for the library list and details when using the device. From what I have seen, it doesn't read the ISBN or publisher from the sideloaded books. But, it does read the published date.
For the published date, the device seems to read exactly what is in the metadata of the file and store that as string in the database. If this is something it can recognise as a date or timestamp, it will display the date part. The timestamp that calibre writes in the date is something that the device was OK with. If it isn't being displayed, something is different in the firmware. What version are you running?
As to the publisher and ISBN, there isn't much you can do. The device doesn't read them, so they don't get into the database. Unless calibre is doing something wrong when it writes the metadata. And I doubt that that is the case.
Right now, there is nothing you can do. Unless you want to update the database on the device yourself. But this might change soon.