What is "Yom ha'Shevi'i"?
Rashi: It is Shabbos. It was the fourth day of the [seven days of] feasting.
Malbim: It was the seventh day from when he said the riddle, the end of the feasting before the Nisu'in. Then she married him, and could probe his secrets.
Why did they say "he will tell us"?
Malbim: They did not intent that they will hear from her, and she will cause her husband to lose 30 outfits. Rather, he will tell them before the time expires, and the deal will be canceled.
What is the meaning of "ha'Leyarshenu"?
Rashi citing Targum Yonasan: It is to make us poor [Radak - via taking our money via the riddle. This is why you invited us!]
What is the meaning of "ha'Lo"?
Radak citing Targum Yonasan: It is 'to here', like Halom.