It depends on whether the stuck lorry was the only incident the FB crew were attending that day. Presumably there was pretty widespread flooding so it would make sense to be out and about with the most appropriate equipment. I also doubt they went out and bought that bit of equipment that morning just for that rescue so any opportunity to be familiar with using it is probably welcome.
It didn’t look deep where the camera was filming from but that truck was in deeper water and looked like it had dropped its wheels into a gully and at the gullies either side of the road the water could be a fair bit deeper and until the water clears you wouldn’t know if the road edges have been collapsing into those gullies.
The road to my house flooded a couple of summers ago, just for an hour or so. It was only about 4 inches deep but fast moving – at any week spot in the tarmac and at the drains either side the water cut trenches 2 to 3 feet deep.