A Monso is listed in the great Glasmarken Lexikon -the bible for glass marks. But unfortunately it says almost exactly what I would have guessed
Basically: French, Enameller, 1930s, and everything else unknown.
There were hundreds of glass houses in France, many of them in Paris, that bought blank glassware and hot and/or cold enamelled them. The majority never even signed their pieces. A Monso is unusual in that they obviously, sometimes, signed their wares. As for any links to Lalique, well Lalique employed a lot of people and I'm sure some moved on, but he did not employ enamelers -so I'm a little sceptical.
Weirdly these types of finishing houses were quite vocal in protesting that their 'bought-in' glass blanks were 'French made'; something I suspect was often not true, in the early 1930 bohemian ones would have been as good quality and probably a lot cheaper. But when the french economy struggled in the mid thirties the price of French made blanks plummeted.
Sorry I can't help more.