1)
What is the meaning of "Hishmi'a"?
1.
Rashi: He made them think that they heard.
2)
When did they hear this?
1.
Radak: It was just before [the start of night, when] the Metzora'im came. Had they fled during the day, Yisrael would have seen this! Also verse 7 says that they fled "b'Neshef", right after they heard.
3)
Why did they think that what they heard was Malchei Chitim and Malchei Mitzrayim?
1.
Malbim: This was part of the miracle. They feared those kings.
