I would put any seedlings that have sprouted under your grow lights now. Seedlings don’t need much light but if they don’t get it eventually they will suffer!
As for the seed that hasn’t popped in ten days, I would dig it up and see if it looks rotted. If it isn’t, place the seed back into a cup of water. Let it sit for 18-24hr and then replant it in your medium. Put it under the light so once the seedling pops it can search for light!