The Centinela location suffered from consistency issues in the kitchen after Sergio left years ago. I think with that and Sergio’s reputation with many of the customers, the number of eaters fell.
I think in an effort to draw business, this location set up a karaoke stage (which doubled as a music system). I don’t know about others, but this single move scared us away from ever eating in their dining room again - really loud and the “singers” were definitely amateur.
The food became more consistent again where many of the dishes we usually ordered while Sergio achieved a “pretty solid” rating from us, including the Pescado Zerandeado. The kitchen staff seemed to stabilize with supplemental help from some of the family members (I recall one of the teenage daughters being taught how to work the grill).
With Sergio’s return, we could perceive a difference in the dishes - not so much the quality and care in the kitchen, but more bells and whistles (e.g. diced mango in the Marlin tacos, additional dishes off-menu).
The down side is we also noticed the seafood didn’t seem as fresh. I don’t know if Sergio’s return was reciprocated by previous customers returning, but we didn’t see it. During dinner, the place was often empty (or maybe one or two tables occupied) when we’d pick up our order.