I think you may correct as I too thought Florence was too close to the canal bank and got caught with bank suction as I can't think that steering gear failure was the problem.LakerCapt
It appears that the Florence Spirit has considerably more headway than the Alanis. I would think that the Florence Spirit failed to slow down for the meeting and got too close to the right hand bank and experienced bank suction which caused the sheer to port, resulting in the collision. If she had reduced speed for the meeting, she may have been able to apply power (a bigger bell) to try and break the bank suction. Your assumption of a steering failure would also be a possible explanation, but I think that bank suction is a more likely explanation from viewing the video.
While I've never practiced the "Texas Chicken" maneuver with a real ship as you've mentioned in your post, I did conduct it many times with the maned models at Port Revel in France and it works very well. We were fortunate in the San Francisco Bay area that the very narrow channels had been limited to one way traffic after several mishaps. The "Texas Chicken" name comes from the Houston Ship Channel where it's routinely utilized with great success.