Am I missing a Bolt?

So, recently I had an issue with the belt tensioner and idler pulley. The belt was slipping off. Caused vehicle to overheat and during that the coolant level sensor came out and coolant was everywhere. So, in the process of cleaning the engine bay area of all the coolant spray, I noticed this hole which has thread inside which seems kind of obvious then that there should be a bolt here? I believe this is the intake. This area is in between the alternator and ignition coils on the side of the drive belt on the side of the intake.

I don't know much about cars, but you've been very helpful in the past. I do have a repair manual and shop manual, but neither really answers my question. My engine bay doesn't look like any of the photos in the manuals and when I look for the bolt patterns in the manual it says there is either a 6 bolt, 9, or 10 bolt patten and none of them show bolts on the side.

I've thumbed through the entire manual looking for any diagram or photo that resembled the area and I did find one but again, the manual photo has the bolt/screw coming out and mine does not.

I don't have any leaking, other than the coolant that was everywhere. The area is wet in the photo because I sprayed engine cleaning foam all over and began scrubbing which is when I noticed the hole in question.

Please advise. Thanks in advance.

Pictures attached.