“Was that wrong? Should he not have done that?”
Apparently not, 8>)
It depends on the kind of weight he was pulling.
His torch cut holes appear a bit oversize, but still sufficient meat for a light load?
The story is in Canada - In the USA it is called Hot Shot towing. A Ford F 350 can tow close to 30K. - you see a lot of hot shot towing with Car carriers, boats, etc. Lot of videos of F 350’s or Ram trucks towing an empty 53 foot trailer.