The Rav Malbim explains the difference between vayosuru and vayraglu. Moshe Rabbenu sent spies to determine the preference of each shevat what land is good for them but they switched their mission to find what is wrong, vayraglu They were suppose to return their findings to the general and not publicize it as indicated by shelach lecha. take ownership of it, explained by Rav Abarbanel and the Maasei Hashem. Even if they told the truth, the emphasis in their report was disparaging by nullifying the preceeded good, leaving at the end a bad taste behind.
It says urei betuv yerusalaim kol yemei chayecha, just see the good of Jerusalem all your life which applies to the whole Israel.
Also they were anoshim, tzadikim who would not say anything bad.
There is a big questiin. what did the children sin to be punishef for forty years being in midbar? They actually benefited to learn from Moshe Rabbenu.
So, why did everyone else cried when they were given an opportunity to stay in the yeshiva of Moshe Rabbeinu for their whole life?! On full support! Would our generation cry or be happy?