As far as I know, none of Einstein's THREE refrigerator designs ever went commercial. Einstein read a newspaper article in 1926 about an absorption refrigerator that leaked toxic refrigerant in an apartment in Berlin and killed the entire family living there. He called up his friend Leo Szilard and said “There must be a better way.” Here are a couple of articles about it:
https://www.wired.com/story/einsteins-little-known-passion-project-a-refrigerator/
https://www.aps.org/publications/apsnews/201011/physicshistory.cfm
He first design used three coolants and was more complicated than a simple absorption refrigerator. The design was bought by Electrolux for $750, but was never produced commercially.
There is now renewed interest in Einstein's design, albeit highly modified. But it's still in the development stage as far as I know.
You are correct, but it's my (perhaps mistaken) understanding that the Dometic brand is a modified version of the Einstein fridge.
Some models can be switched back and forth between electricity and propane/kerosene.
As I said, I could be wrong.