Check AFM page 1-20
Link
http://www.diamondaircrafthungary.hu...m/DA42_POH.pdf
It is certainly RNP5 (BRNAV)
It's AMC EASA 20-4 compliant
You're answer will remain within Diamonds certification, as it's part of the 'overall' package.
I don't think it will be PRNAV approved. Do you have an operators LOA for PRNAV and a company or school manual for this? The aircraft is, but are you guys? So, it COULD be LNAV/VNAV and LPV if you have approval.
I would urge you to do your own research on this. Take your instructor for a beer.
Also can you do a RAIM prediction on a DA42 panel fit?
Read page 18
http://www.ecacnav.com/downloads/P-RNAV30-07.pdf
P-RNAV approval here page 9- something
http://www.diamond-air.at/fileadmin/...15e-A33-r1.pdf
Hope this helps