I dont remember all the particuliars, but a few yrs ago when Boymalgreen(? on teh spelling) ran into money problems ( he owned most of what then were the Starwood Hotels in Israel) and I believe Fattal was a partner. Fattal took over the Hotels and then exited from *W. At the same time Fattal announced expansion into Europe and wanting it to be somewhat of an Intl chain.

So Im not sure if Leonardo existed before Fattal tookover Boymalgrens props (which it was a partner in) or was the result of the take over as well as what you say was a merger. I think Fattal already owned the hotels in Europe just not as numerous as they are today.

Could be Fattal needed/wanted a new name for its chain of Hotels in Israel and went with the name they were using in Europe = same pair of pants just 2 different pockets became 1 pocket. No real merger of 2 differently owned Hotels, Fattal owned them all

fwiw, the Novotel chaim in Israel was also owned by Boymalgreen and taken over by Fattal as I believe a 3rd one was as well, thats why in some locations there are several Leonardo's today