When Howard and Madeleine are talking on the sidewalk of the street in Manhattan, traffic is moving swiftly while the camera is in one direction, and traffic is completely stopped when the camera is in the opposite direction.
When Howard is talking with Claire in the street, the weather changes from sunny to fully cloudy.
There are two explanations for why Love, Time, and Death were not seen in the videos. One is that they were removed with editing software. That would be true if they were only actors. Otherwise, they could actually be Love, Time, and Death pretending to be actors, because they were also helping Howard's friends with their issues. The PI was hired to follow Howard, so would film any action on his part. She may not have seen Time, Love, or Death because they can appear to whomever they wish and remain invisible to everyone else. They only interact with the main characters.
Takes place around Christmas in New York and during close ups there are clearly piles of snow against the curbing, put there for effect. Yet a flyover displaying all the streets in the city reveals not a speck of a snow. Was obviously filmed during a warm time of year.
It's unlikely the P.I. would be in the exact location to film Howard berating "Time." There would be no way for her to know when, where, or if he would stop, even if she knew the plan was to make Howard do so.