AinOhdMilvado:- What an incredibly smart piece of advice. I absolutely concur with you.
Let them go next week, and they can spend Yom Yerusholayim & Shovu’os in Yerusholayim in the Jewish Quarter & pray at the Kossel.
Then for the remainder of the summer, when it gets hot, go for 3 days to Tzfas, which cools off nicely in the evenings, even during August.
This week’s Parsha of BeHar in Israel, is the source for giving business to a Jew rather than a Nochri, when not going to hurt oneself financially doing so. This Halocho certainly applies to vacationing in Israel rather than in Switzerland.