Germination in cotton pads covered with plastic foil 5 days in dark place with constant temperature of 22,5 °C. 4 of 4 success germinated.
Don't over soak seeds. Important to spray one time maximum 7 sprays of water on lower pad and 7 on upper and left for 3-4 days until you touch it again.
About a week or so. Probably caused by over or underwatering in the first 2 weeks. They should recover and produce well.
Could also be genetics of course.