Enamel tray signed Rob Grun or Kob Grun

Nice as these enamel trinket trays are, they don't seem to sell for a whole lot, but couldn't help but grab this for a few dollars. Totally eminds me of Steinbock email (enamel), but it's not stamped Steinbock, instead has an artist's (?) signature, or maybe the person who did the gold paint? Anyone recognize the maker? Thanks.

 

rob , I'd think..

 

sure does resemble this stuff....
https://www.ebay.com/itm/387244080704

 

I have a new theory. Many of the Steinboch pieces are white on the back side with "Steinbock" mark printed in black. But I just found one on Ebay with a blue enamel back and a sticker rather than a stamp:



Maybe someone removed the sticker and wrote their name on the back for some reason, like to show ownership in a family or something along those lines?? Although the number that follows doesn't really make sense... Or maybe it's the name of someone who worked at Steinbock?

Not going to spend too much time on this one. It's pretty, maybe that's all I need to sell it.