Maurice Allais invented the paraconical pendulum around 1950, this, not a Foucault pendulum, is what is used in these eclipse experiments. From your own link a quote from his autobiography "On the experimental level, and as a by-product of this theoretical research, I conducted, from 1952 to 1960, experiments on the anomalies of the paraconical pendulum (a short pendulum, about one meter long, suspended by a steel ball), anomalies the existence of which I proved. For these experiments I received the 1959 Galabert Prize of the French Astronautical Society, and I was laureate in 1959 of the United States Gravity Research Foundation."
As you can see not a Foucault pendulum which you correctly described as "....to work well it needs to have a very long wire".