Looks like the dog simply picked up the end of the hose from the garden to hold it in his mouth like a toy, of course completely oblivious to the water coming out of it, therefore mindlessly "powerwashing" the TV and the rest of the room as he walked around.
If the TV wasn't plugged into the mains and then allowed to really thoroughly dry out over at least a week with the back removed, then maybe, although the speaker cones are made of paper and hence likely ruined. However, being plugged in, corrosive electrolysis would have taken place that would cause serious damage to it. Don't do it, kids.