Lower-bound conjecture for deterministic locating-dominating sets on the infinite king grid

Let $K$ denote the infinite king grid, and let $\operatorname{DET:LD}(K)$ denote its deterministic locating-dominating density. Deterministic locating-dominating density conjecture.

$$\frac{15}{44} \leq \operatorname{DET:LD}(K).$$

The authors believe this can be proved using techniques similar to those already developed, together with a discharging strategy. The conjecture concerns improving the known lower bound for deterministic locating-dominating sets on the infinite king grid.