Thanks for reaching out to the Bose Community. Welcome to the site.
This may be possible, but you will need to use a DAC (Digital to Analog Converter) to enable the functionality. By default, the digital out is as its name suggests, digital, whereas AUX is analog, and can only understand analog-based signals.
While I cannot make any non-Bose product recommendations, other members of the Community may be able to advise based on previous purchases.