Likely the bolt made it all the way to the bottom.

Personally I would remove the lower oil pan and look up with an inspection mirror to see if the bolt is laying on the ledge right below the crank sprocket. That would be an easy quick fix since you can just reach in with a magnet and pull the bolt out. Would only take about 30 minutes to pull the lower pan and the oil pickup baffle and look up with an inspection mirror and flashlight AND put the lower oil pan back together. Lot quicker than the 4 hours or so to speedrun through taking off the timing chain cover, 8 if you've never done it before.