Calm down. If you don't agree with what I'm saying, just tell me why. I'm just trying to get a conversation going.
i'm perfectly calm, i said it because you have a habit of wanting this or that detail within the canon or a story to be true, and go through overconvoluted hoop-jumping and reaching to the point of driving yourself crazy trying to justify your desired narrative when occam's razor usually answers your questions from the onset
but if you insist:
and remove any marks you have made upon the land.
You had your chance.
neither one of these mean anything at all
we see him immediately after his kindle fire skype call declare that it'll take him a year to raise an army, meaning that his intention from the start was to kill everyone
meaning that these "outs" you're wondering if he offered the city were nothing but lip service since the outcome would be the same regardless of whether or not the "offers" were taken
he gave them a year to make peace with god, think about what they'd done, and come to terms with the fact that when the year was up he was going to kill them all
that's the long and short of it--the people were basically told to come to terms with their incoming deaths a year in advance, and nothing they did would've stopped or changed it
that's it
now if you want a more poetic or narratively less-simplistic reason, i have my own conjecture based on his interaction with the old woman
perhaps he DID offer a way out, despite his unrelenting fury in the scene with alucard strongly implying the opposite as listed above, and raised the army anyway to follow through on his threat in the event they didn't take the way out
something akin to "well i'm gonna raise a hell army, but if you can show me in a year that you can repent and make amends for the sin committed against me, maybe i won't kill you after all" or something
cue a year later, and everyone's instead treating that sin like it's carnival or some shit, so he follows through as he said he would
this is also largely what i believe to be the cause of his change from "kill wallachia" to "kill everything"-- if he can threaten humanity with unyielding and merciless genocide if they don't clean up their act, and they
still carry on like nothing happened, then fuck it they all deserve to go
or, another idea, and one a bit more probable given how absolutely pissed off he is after giving the initial threat (you don't tend to genuinely offer mercy when you're that angry, after all), the "way out" of the threat was all a lie from the beginning
a ruse to give him an excuse to (essentially) gloat just before unleashing the onslaught, and justify said onslaught to himself, because he knew damn well they weren't gonna make peace or repent or any of that
he's the big bad evil villain after all, it's not like it's in his contract to be honest with his enemies
i'd lean more towards this second conjecture, as his unbridled rage as well as certain lines like "there are no innocents, not anymore" doesn't exactly paint a picture of a guy willing to show any mercy to those he wants to kill