Explanations of deontological responses to moral dilemmas

deontological responses ... arise from some sort of error, or poor thinking.

I don't understand the complaint. Deontology is simple: you just apply the fixed rules. If in a particular situation the fixed rules lead to an undesirable outcome, that's too bad but that's how deontology works -- it is explicitly NOT consequentialism -- and that has nothing do with "poor thinking".

...deontological responses (DRs) seem to be equivalent to responses that demonstrate cognitive biases in non-moral situations. For example, the omission bias favors harms of omission over less harmful harms caused by acts, in both moral and non-moral situations (Ritov & Baron, 1990). This similarity suggests that the DRs arise from some sort of error, or poor thinking. Much evidence indicates that the cognitive processes supporting moral and non-moral judgments are largely the same (e.g., Greene, 2007). If this is true, the question arises of what sort of thinking is involved, and when it occurs.