Apple - Upgrading to 32GB RAM for Mac mini Server (MD389LL/A)
No. That Mac mini is limited to 16 GB max ram.
You can be pretty sure that if it's not mentioned in Everymac or sold by OWC[MacSales] or ramjet.com, it can't be done. These reputable sellers will always provide good research and advice if more memory can be used past Apple official specifications.
Whether you would choose them as your vendor or not, they tend to cover all possibilities & often support things that Apple never intended.
Anyway, I'm afraid I have some bad news for people hoping for more than 16 GB total memory.
Due to an intel Core i hardware design defect, seems to have been fixed only for 4th or 5th generation Core i processors, the previous generations won't take 16GB DDR3 modules although the parameters for such modules were established within the original DDR3 specs.
So, it should work, but it doesn't.
Intel's fault.
Sorry.