MEK or MER mark? - Maureen E Koppenhagen-Rothstein?

I found these 2 tactile and visually appealing bowls in East Devon recently. The BISPM website has a photograph of the above Potter's mark suggest they are by Ms Rothstein. Only one bowl is signed. Your assistance is much appreciated, thank you

I’m seeing HEG rather than MER or MEK, and it seems to be incised or at least indented, rather than a stamp.
The Maureen Rothstein mark below for comparison. Unfortunately there are no examples of her work, but it looks like a different clay so I think it’s unlikely to be by her, imo . (The Marks book says she used MER and MEK before and after marriage).

Thank you so much for your advice. I understand what you mean about the marks. I did study them hard and yes they are hand written and not a stamp. I think the first letter is M because I believe it was written in one movement upwards to top of first stroke, then down, back up then down for last stroke, if that makes sense (rather 2 perpendicular strokes with horizontal cross). I had looked everywhere to see examples of Maureen Rothstein's work but as you say difficult to find.

Thanks for your invaluable advice as always.