I had to go back and get a better view of this thing. YouTube clip here:
https://youtu.be/o2kA0mkb7x8
I think I was right that it was indeed a trailer to haul a bob house. Clearly cut in the floor are two square holes, one for each fisherman.
Based on the gauge of steel etc. this is a well built home-built affair. Car tires, heavy welded angle iron frame, some stainless hardware.
Cusk still there-they sure do like structure.