It would help if you knew what you were talking about, but the odds or any other american knowing anything about Lambeth are next to 0. In fact, the odds of the average american knowing something about Europe or their own country are also pretty low. Just a few days ago an american asked me for information about how to get to France by train. I asked where in France he wanted to go and the guy replies: 'what do you mean where in France? France, the city in Paris'. I told him to get on a plane and go back to Michigan, the city in the state of Detroit. He took him a while to catch on.
Lambeth (and a good chunk of Kennington) were heavily bombed by V2 and V1 rockets in WW2. As a result, a very large portion of the buildings in the Borough are currently council houses, so in essence using Kennington for that joke was either dumb, ignorant or a symptom of something worse. It is more or less the same as joking using US neighbourhoods noteworthy for crime or racism. But hey, we don't know you and as an american we can't in good conscience assume you'd have a problem using a 43yo black mama from Ferguson for your jokes instead.
Actually the Ferguson equivalent has 14 OD and 11 ID with 10 SB so she would have just swatted those shots into the 6th row. Injuries in the game are somewhat random, then again so is real life.