So, not gonna lie, this isn't what I planned on doing today, but, here I am.
So, the Broome Titanosaur. As I mentioned in RDS 2, it would not weigh 800 tonnes, or even 500 tonnes, even at 80 meters long. If you want an explanation for this, go read that post. Anyways, this image is based on Paralititan:
But Broomey here would probably be more Puertasaurus-y, because larger creatures require proportionately larger organs to function, and thus would have a much wider chest. In which case, it would weigh about 300-350 tonnes, or about 330-385 tons (I did say in RDS 2 that I scaled off of Puertasaurus, so the weight would be the same). But, this image looks a bit different.
This one looks more like modern reconstructions of Argentinosaurus, albeit with a more raised neck. Such as this:
So, the weight would be, actually about the same, a bit higher, maybe about 330-400 (363-440 tons) tonnes simply because the torso makes up more of the body length. However, I find an 80 meter (262 foot) sauropod highly unlikely, more likely the feet were as big as they were (about 1.75 meters, or 6 feet wide) to help it more effectively spread it's weight. I remember somewhere I saw 54 meters (177 feet), in which case I'll use that. I'm scaling from Puertasaurus for this. In which case, about 150-180 tonnes (165-198 tons). Of course, even the existence of a 54 meter sauropod is unlikely, so take this with a grain of salt.