there was a problem that the internaLocations endpoint doesn't return label property, whereas every console.log, even console.log written directly under the fetching method, was eventually returning objects with label property, whereas while mapping them, the label was undefined 🤔
It was misleading in the debugging, hence I even asked GPT - it turned out that JS does some quirk with console.log, when we mutate an object later on:

This is why I prefer immutable approach in programming.
FYI: console.table was returning the real value, not the "If the object is later mutated (like by a component or somewhere else in your code), it reflects that mutation even in earlier logs."

The real mutating happens in the Select compoment in the mapOptions method:

mapOptions(values) {
    return (_.map(values, (value) => {
      const newValue = value;
      if (typeof value === 'string') {
        return { value, label: value };
      }
      if (value.options) {
        newValue.options = this.mapOptions(value.options);
      }
      if (value && this.props.labelKey && !value.label) {
        newValue.label = value[this.props.labelKey];
      }
      if (value && this.props.valueKey && !value.value) {
        newValue.value = value[this.props.valueKey];
      }
      return newValue;
    }));
  }

so even if you added here something like:

newValue.test = '123';

the console.log that would be put directly under fetching method, would already log the objects with test property 🤯