No, Henry Jackson, Joseph doesn't seem to have the same marks, but the picture in Langdon isn't very clear.
I didn't keep looking after Jackson, as his are certainly the same. I have never really studied the later Canadian silver, as I am mostly interested in the French silversmiths. I think however in some manner they often shared marks, I don't know if there was any control or not. Jackson's leopard has the same funny left ear, so either they worked together, or one inherited the marks from the other, or they were some kind of control