It depends on who you meet first, I think... if you make a hostile action towards Vlad I think he'll remember it even if you become friends with Ivan. But Vlad IS Ivan's pet.
No... Well I have, but not the god code. I recall Ighalli (or was it one of the devs?) saying the above at some point. Or was it in the first Wiki? I can't recall.
I'm about 90% certain you do not. It's a chance thing. You need at least 500 (out of 1000) favor, and the chances of getting it with each prayer increases with your favor. So a champion will be far more likely to get it than a 500-favor person, but there is a slim chance the 500 person will get it too.
Actually the super-accuracy of whips is pretty well known. Or at least, it was. Whips are probably my favorite weapons.
As for the non-breaking of them... well that's because whips are invincible. There is no such thing as a "broken whip", thus you can never destroy a whip (save by sacrifice). Petrus decreed this 700 years ago, and it has been thus ever since.