I know I'm a bit heartless and hard on the refugees here, but it is them, who directly run into the forces of their enemy. Nobody right in their mind should expect them to get any help in this kind of situation, if they don't act first. Either they have to go back, secretly circumvent the blockage or make a break for the border through it. But even in the later case, they shouldn't expect to be greeted with anything else, than hostility by Almus forces, too. (It is thinkable, that even a neighboring lord, you want to flee to, would give that order to avoid a war.) It is one thing, if one's life it threatened, but it is another if you also brought the immediate danger onto yourself (no matter if the reason is to escape persecution or not) AND expect others to lose their life in turn to save you from that kind of situation.
They fooled themselves into believing there is an easy solution for their problem (wise ruler Almus, with shit tons of mighty, immortal solders and free land, just over that river, that will surely take them in), risked everything and now can't coop with the outcome. (In their shoes I might have done the same (fleeing the Diebel territory), though I want to believe I would have taken another route, as soon as it become clear it doesn't work out.)