Error processing component - how to override message?

We are running some line charts against many potential sets of data. In a few uncaught cases, the data set might be empty/invalid. I'm trying to check for errors with the following code in PostFetch:

var cccOptions = this.chartDefinition;
var eps = Dashboards.propertiesArrayToObject(cccOptions.extensionPoints);

eps.noDataMessage_text = "(No data found - chart cannot be displayed)";
eps.invalidDataMessage_text = "(No data found - chart cannot be displayed)";

These work most of the time; however, I am getting the following message in some cases: Error processing component(chartname). The cda shows that there were no data results. I would think my current text overrides above would work in this instance, but is there another extension point I should be targeting?

Thanks in advance!