Unfortunately I can't read the text, but be careful of the sync voltage of those disposable camera flashes. The ones I have are over 100v so it makes it harder to trigger. I think a lot of people use a SCR or optoisolator to separate the high sync voltage from the camera.
I am very curious about how you trigger it, I guess you turn on the USB power + flash at the same time and you didn't use a optical slave trigger