Double Golden Angels Trumpet Seeds

Despite cold stratification, no luck with the seeds. I know they are hard to grow, but still disappointed.

I planted these last year and had 2 plants grow - and boy did they grow. I started the seeds indoors and eventually plants into the garden. They grew over 6' tall and were covered in flowers. I am ordering more this year. I did try to get the seeds from the plants but I don't think they dried out enough before the cold and snow hit them.