There was an overlap in the timeline and bear in mind, that the B-17, from it's inception, through the later variants, had provisions for external bomb shackles that could have easily accomated torps.
Also, Kenny (and Pappy Gunn) were notorious for doing what they wanted, much to the disdain of the "boss".
This included using B-17s for skip-bombing, which got their asses chewed, but when the word went up the chain that they were corn-holing Japanese shipping, the heavy breathing from the brass backed off.