Buenos Aires donor plaque information requested #latinamerica

Ittai Hershman

With the recent links to AMIA and CEMLA databases for Argentina, I am trying again to solve a mystery I last posted about a dozen years ago.  On 3 May 1939, my cousins Schmul Hersch and Sara Horenstein arrived in Buenos Aires from Berlin via Southampton on the ship called Asturias.  Schmul Hersch, known as Henio, had a brother who lived in London whom I knew.  Their father Mendel survived the war in the Jewish Hospital in Berlin, and after he was found, joined Henio in Buenos Aires where he later died and is buried in Tablada.  I have a photograph of Mendel’s grave that, as I recall, a kind JewishGenner photographed me.
Henio’s wife was his cousin with the same surname before marriage.  She was known as Sala in the family, and as you can see in the attached, she also seems to have gone by Mara.
Some years ago now, I visited the daughter of the brother in London who knew that her aunt and uncle in Buenos Aires had by then passed away, but had no details.  She provided me with this photograph of a plaque at some presumably Jewish institution in Buenos Aires, possibly in the Merlo area, but I have never discovered anything further about their deaths or burial.

Can anyone identify the location of this plaque or anything further about the donors?
Many thanks for any solid leads,
Ittai Hershman
New York City