safety chains

I bought my first truck camper sometime around 1975. Since then, I have owned a camp trailer, a travel trailer, I lived in a fifth wheel for three years, I have owned 4 different Class A motorhomes, one Class C motorhome, and a couple of other truck campers.
I have never met anybody who lost a trailer of any kind while moving. I have never met anybody who lost a towed vehicle. I have never met anybody who dropped a fifth wheel on their truck box. I have read about one instance where a trailer on the freeway got away from the towing vehicle (it was on the wrong size ball, no safety chains were in use, and there was no breakaway brakes in use).
Having said all that, I use safety chains on all towed rigs. They are attached to the receiver safety chain loops. I have never needed them, but they are there, and hooked up!
Safety chains or cables should always be connected in front of the most likely failure point on the towing vehicle, and behind the most likely failure point on the towed unit. ANY damage to the chain or cable is cause for replacement! Remember, "A chain is only as strong as its weakest link!" A damaged link is a weak point. the same applies to cables, even though a cable has no links; any damage weakens the cable!

As others have said the chains should go from frame mounted base plate to
frame mounted hitch. Both should have required attachment points. The tow bar should not be in the picture.
I have a 4 inch drop hitch which increase my chain length requirement by almost a foot over standard chains. I installed 18 inch safety chains to both sides of the motorhome hitch. The standard chains connect to them.

Just keep in mind, in 50 years of RVing I've never KNOWN anyone who has had a travel trailer that was disconnected accidentally. IN that same time frame I personally know of three people who have had a towed become disconnected. ONE of those times another family was seriously injured. Please be safe.

x2on above info. If towbar breaks loose, where is toad going?
I had to purchase a new set of safety cables for the my toad and there were 2 different lengths for the Blue Ox. I use the longer cables.

Your safety chains on the MH must be connected to a frame bolted item.
I would suggest getting the safety cable extensions to run from under the MH to the point where you can get to the regular safety cables/chains.
Safety cable info

And if the Pin for the extension should just happen to come out?
Once you hook up the chains on the MH. Just leave them joked up.