Most Langham Paperweights are acid etched or sand etched Langham England on the base and the labels are on the side.
The words Langham and England are usually one under the other, so the word Langham is possibly under the label.
Most signed pieces have Paul Miller's signature, and I would have imagined that this would be seen either side of the label if it was a signed piece.
I suspect that the label was moved to the base so that it did not interfere with the design when the paperweight was on display.
Have you tried looking down onto the weight to see if you can see any further writing through the glass? This should be quite easy to do as it is not a very complicated multicolour design.
If all this hasn't helped, then as Christine suggests, ask Langham Glass House, I have always found them to be very helpful and friendly.