The only dps to pdf conversion we know about, is export of old Kingsoft Office presentations (or their texts) as PDF documents. This will be incredibly hard to achieve nowadays, unless you have access to the original software. Pretty much every alternative software does not support Kingsoft formats, with the exception of some Linux tools. So your best bet is to actually find old copy of Kingsoft Office, or installation package on one of the abandonware websites.
Updated: August 24, 2023