So I'm just back from viewing this car in person.
No, I don't believe the seller knew too much about the rust underneath prior to the visit from the other person who took pictures. Just my hunch. But yes both front subframes are in the same bad condition. There are also several other rust holes in other areas of the body - rear quarter panels and above the trunk, and the front passenger fender pinch weld on the bottom rear is pretty much gone too. Yes there is some rust underneath the vinyl top right above the rear, but I would say not as bad as it may seem - mostly solid but I also didn't peel up any vinyl either. Some leaking and resultant rust in the trunk too, which the seller did tell me about and then showed me.
Bottoms of doors both inside and out are pretty solid. One sounded like it had some filler but easily passed the magnet test and I didn't see any evidence both inside and outside; one door bottom did NOT pass the magnet test for a spot in the middle bottom, but looked good on the inside and outside. I didn't see any glaringly obvious signs of repainting or repair. The far rear driver quarter panel is slightly dented too.
The inside is actually not bad at all! I was expecting musty and didn't get it on an 87 degree day today! Yes it has been outside for some time and will continue to be so, and yes there is evidence of some critter infestation - not bad but certainly some - but there are also lady bugs that have moved in and like this spot! So I believe the air fresheners were there but aren't doing too much - they are years old. The top of the dash is covered but looks really good underneath; there is actually cruise control (you can see the actuator under the hood) but not stock control for 1970 - and I'm pretty sure this is a pivoting column as there is a slight angle break to it, so I'm guessing that the entire column was swapped at some point, but it does NOT have the control handles for pivoting, probably removed (for who knows why?) I am guessing. Looks like it has the lighting package - turn signal indicators on fenders, light in glove box, and map light (switch on dash is broken however).
3 hubcaps and carb and manifold and air cleaner (sans engine identification) in trunk; one other hubcap on car; two front tires have date codes from 2022 and couldn't see the codes on back tires, maps and other paraphernalia in glove box indicate a local to MN car for some time; oil change from 1999 and just a few hundred miles less than now also close by in MN; MN Park Pass on windshield from 1970 so it was at least purchased here I would bet; also MN collector plates but no tabs on them - we have to renew tabs every year in MN and put them on plates to legally drive.
Was sellers' dad's car, who passed recently; seller didn't really see his dad so didn't know too much about it; no known reason for manifold nor master cylinder removal. Seller says they did power up with a battery recently (I did not witness) and the lights work; they turned the motor over by hand, no idea if they tried the key/starter; seller does have the key(s). Missing are the brake booster and master cylinder and coil.
Too much for me with the subframe damage, nor do I have a good place to store it anyway, but otherwise there are a lot of good things on this car other than the front subframes. And I love the look! I had a 1971 4-door Newport 4 door wayyyy back (40+ years!) so maybe I'm a bit biased too.

Proof of how big these cars are? We had like 12 or 15 cases of empty beer bottles (when cases were also returnable and reused along with the bottles, remember 40+ years ago...) and stacked them all in the back seat - and it didn't even come above the front seat so didn't restrict rear vision in the least! Not sure why we didn't put them in the trunk.........but probably because I lived in Buffalo NY at the time and we were returning the empties to Canada (oh for the days when you didn't think twice of going through a border crossing just to purchase beer or return empties!!).