I just fished a couple of alarm clock LED panels out of some junk I was binning and have checked them but they are;
B) The same pinout as the one in the bottom picture of your pin-to-pin diagram near the top of the thread.
Congratulations on the repair though.
If I may add to JJL's description of how these things work;
The multiplexing is actually done at 50HZ for good reason, the 2x commoned cathodes (alternatively they can be anodes in some designs) are connected to both ends of a Centre tapped mains transformer, one of the ends also goes to a special pin on the clock chip.
When the mains goes negative cycle (in this example) the clock chip detects this and outputs the appropriate segments for that half of the mains cycle and the LED's connected to the negative going side of the transformer all illuminate, meanwhile the LED's on the positive going side are thusly prevented from illuminating. On the next half of the cycle the exact opposite happens and the whole thing continues for ever and ever.
As well as using the mains to sync the display, it's also used as the clock source, as per older mains clocks with synchronous motors
And as such, the clock chips usually have a pin dedicated to 50/60Hz switching for UK/USA markets.
Take a look at the following interesting link where the author tears down and builds another clock (in a later posting).http://blog.tynemouthsoftware.co.uk/2012/12/led-clock-part-2-teardown.html