Request for a Temporary Mathcad 15 Evaluation License for Compatibility Testing

I would like to request a temporary evaluation license for Mathcad 15 to perform local compatibility testing of a software integration demo. I already have the Mathcad 15 installation package, but I do not have a Mathcad 15 license. I have completed testing with Mathcad Prime; however, its trial license cannot activate Mathcad 15. I now need to separately verify compatibility with Mathcad 15, including opening and saving legacy worksheets, modifying input variables, recalculating worksheets, and retrieving results through its automation API. I understand that Mathcad 15 has been discontinued and that the previous trial licensing links are no longer available. Could you please confirm whether a short-term evaluation license can still be issued for this purpose? If not, please advise whether there is another authorized way to carry out this compatibility testing. The requested license would be used solely for local development and evaluation, not for production deployment. Thank you for your assistance.