Another plant from Kew Gardens in the Princess of Wales conservatory that I couldn't find a name tag for. It looks to me like a giant version of the wood spurge I have that grows wild in the garden but It could be something completely unrelated. It was near all the Bromeliads if that helps and it was at least 6ft tall.
Shoot I have to guess Pittosporum, Japanese Pittosporum. pittosporum spp. My first guess is usually right but not so much lately. Yours is lanky because it is in a bit of shade. Do you remember any flowers? This plant also loves acidic soil and because it looks like it is right next to your foundation, it isn't as happy as it could be.
Green Pittosporum or Mock Orange There is at least one other plant not related at all called Mock Orange.
Couldn't find the pH this plant needs but fairly sure it is acidic. Looks like concrete foundation or walls...lots of lime.
They love great drainage and lots of water. Too high of a pH and drought will make them look lanky like this.
Let's see what the others come up with...