Trivia: The first time we see Riggs in his trailer, there's an advert for some new aftershave called "Hero" on the TV. During the attack on his trailer later, there's a close-up shot of a bottle of aftershave being destroyed - freeze-frame it and you'll see the brand: "Hero" again.
Trivia: When Leo is cleaning Riggs' house, you can hear the song "I'm Not Scared" by the group Eighth Wonder. Patsy Kensit, who portrays Rika Van Den Haas in the movie, was the lead singer of the group.
Trivia: Right before Rianne's commercial begins, a Tales from the Crypt episode is on the TV. This is the second episode of the first season, titled And All Through the House about a woman who kills her husband and is terrorized by an escaped mental patient dressed up as Santa. The murderous woman is played by Mary Ellen Trainor, who plays the psychiatrist Stephanie Woods in the Lethal Weapon movies.
Answer: This scene is already in the movie (maybe only the Director's Cut). Riggs surfaces just off the pier, picks up a chain, strangles one man with it and breaks the other man's neck. The scene is cut considerably for play on television and in all versions of the movie in the UK prior to the 2010 UK blu-ray release (including the Directors Cut) - although some TV airings since 2000 have used the full uncut version.