Identification of Mammillaria from Lanzarote garden cacti

Hello. I submitted a question about the identification of a Mammillaria exposed in a cacti garden in Lanzarote, identified as Mammillaria karwinskiana. I did it in the 'Other collections' section, because another user had published the same especimen I am in doubt in that section, so I take advantage of that to expose my subject. The problem is that nobody has answered, probably because that section is not so visited like this one. So I have thought to put a link to the question in this thread, expecting get some suggestion. So there it goes. The link is:

https://mammillaria.forumotion.net/t2153-jardin-de-cactus-lanzarote

Regards,