Implied Question: The Gemara in Sukah (51b) says that Alexander of Macedonia killed them and destroyed Alexandria of Egypt. (Note: How could our Gemara say it was Adreinus?)

Answer: Perhaps it was settled (and destroyed) twice.

Implied Question: The Gemara says in Avodah Zarah (18a) that Rebbi Chanina ben Tradyon decided not to hasten his own death, as he said that better that The One Who gave it should take it, and I should not injure myself. (Note: How can we reconcile this with our Gemara?)

Answer#1: In our Gemara, they were scared of being tortured. This is as the Gemara states in Kesuvos (33b) that if they (Nevuchadnezer) would have tortured Chananyah, Mishael, and Azaryah they would have bowed down to the statue.

Answer#2: They would have made them have forbidden relations and would not have killed them (see Yavetz here). (Note: They therefore killed themselves so they should not transgress this cardinal sin (see Tosfos and Ritva in Avodah Zarah 18a).)

Implied Question: The Gemara only quotes six Pesukim, and does not quote the seventh Pasuk (that the seventh son said). (Note: What was the seventh Pasuk?)

Answer: The Medrash says that the first son said, "I (Am Hash-m)," and the second said, "There should not be for you etc." (Note: This is the text of our Gemara, which Tosfos apparently did not have.)