Our officer never refuse any visa application at the counter. INIS is the only person who can make decision on every visa application whether to approve or refuse.
Please check with your representative who attended the Consulate on that day again for an accurate information. We have the records at the Consulate that your girlfriend's application was returned because of she didn't have an online visa application to submit on that day.
However, we have given her some general information that a Study visa for Ireland is now very difficult for Thai person and takes long time to process. If she wishes to apply for a study visa for Ireland, we are happy to accept her application if all documentation are completed.