Yes, but on the examples with the "artist mark", the word Mdina is also written, so that can be compared.
What we got from that thread was that the artist marks were made by either Marie or Dobson, and how each of them wrote Mdina, and that Marie had the spikey writing, Dobson the more rounded.
This was contrary to what I'd been told, which was that Dobson had spikey writing and the rounded style was Said.
The spikey writing looks a little bit more like Michael Harris' writing, but not enough that they could ever be confused. It's a lot bigger and more coarse, just for a start.