i'm pretty sure you've got a keiki with a spike. Congrats!
wow! keiki with a spike? I never heard of it! so does this mean it's going to eventually get leaves too? I thought spikes were only produced by mature growths?!
I've seen it happen plenty on phals, so why not a den? Yeah, eventually it'll grow leaves and the roots will become longer and plentiful, at which point I'd detach it from the mother plant and pot it up. Keep us posted!