Qhaysh is soft power.
Just, you know. The "we have nukes" sort of soft power.
As a political science major, that is NOT what soft power means. What you describe is what is colloquially known as gunboat diplomacy.
Soft power is subtly affecting the amicability of other countries (usually via art affecting the culture, e.g. Hollywood, but any non coercive method is technically soft power) so that they become more amenable to your way of doing things.
Using threats, even soft and understated threats, even threats you do not bring to the table for moral reason but which are nevertheless known to others can never be considered soft power because it is inherently coercive.
It's also worth noting that we technically don't know if there's only one Shallya.
A lot of the seeming schizophrenia of the Warhammer deities and their associated cults vanish if you assume that there's more than one entity granting miracles in each deity's name. It also explains why Ranald can accept the Humble Ones in his flock while not being a complete arsehole to Mathilde for her alliegiances.
We also do not know how powerful a god is. A king or state are not necessarily all responsible for everyone that serves under them, for various reasons, even if they are to be assumed as purely benevolent.
examples: 1) lack of knowledge of the problem, which could be a thing if gods are too big picture to notice everything, 2) picking one's battles to maximize results for maximum benefit, which in a world with chaos gods could be very reasonable, the god could stop benefitting offenders, but actually using the energy to smite anyone but the most heinous or those who seem to be gaining too much influence while wrong could be too much. 3) Having very sharply defined red lines acting as laws, and only going after someone who crosses them outright rather than just those who displease them because that is how a society is supposed to function. Unlikely to be the case with a god like Ranald, but could be true for other gods, especially law gods.