Fren, observe the passing of MARS in the month of Mars. What think? Supposed to be excellent visibility. I have always considered your SV evidence the best and primary. Mention of this Mars proximity should neither control the dig or contribute to confirmation bias, or its' converse. See pics. Observe the transit of Mars relative to Moon. I have looked and cannot see Mars in ROT1. There is poss of it being obscured by structure of LE though.
Okay, now we are talking. My thoughts were that "bad influencers" to our motorcyclist's vector would be (in BLUE) from VICTORIA merging right or from WHITEHALL PL. like the dark car waiting to enter traffic in the Q pic. That car could dart out causing other cars to instinctively veer right, and across our motorcyclist's path, causing him to run into the kerb (in YELLOW) and lose control (in RED)?