Hi Anton,
I have fit PVfit's single-diode model (SDM) from this module's spec sheet. Based on fits to other modules with IEC 61853-1 datasets, I don't think the fit is horrible away from STC. I'd be willing to try to likewise fit PVsyst's SDM as defined in pvlib, if that would help you out. I think it could make for an interesting comparison of SDMs, but I can't guarantee I can make the PVsyst fit work until I try :). Also, because the two SDMs' implementations are pretty close, I would guess that each fit will suffer similarly from the same lack of information away from STC.
Mark