1)
Who came to her?
1.
Rashi: Everyone who dared to. Radak ? the singular is used, i.e. every Nochri. It is one of eight words that refer to Bi'ah of Rabim, but the singular form is used.
2.
Malbim: The illness Balah came [on Ahalah and Ahalivah, like their Husband's curse].
2)
Who are "Ishos ha'Zimah"?
1.
Rashi: Women of Zimah. Radak ? this is the only place where Ishos is the plural of Ishah, for detriment; elsewhere, it is Nashim or Neshei.
2.
Malbim: This illness is called so. It is fire that burns according to the Zimah and great adultery. It is known nowadays as a burning, lasting Tzara'as and decay that clings to adulterers to wear out and burn their bodies and bones.