I didnt read all the posts, so maybe i repeat, but try dry stratification. Just put your seeds in a plastic bag, no water in, and put this into your fridg at 3celcius for 5 weeks. After, just put the seeds in your moist media, on the surface. Blast them with massive lighting, relative humidity and heat.
Over the years, i have 95% germination rate with this method.
Hope this help!
Ps: if you need to use neem oil, you did something wrong, like not enough ventilation or else.
I speak from my experience, feel free to disprove !