It looks like Jack Smith probably has phone records/messages, surveillance footage, and/or cooperating witnesses for Trump's plot to delete the security footage at Mar-a-Lago.
The indictment indicates that Trump called De Oliveira and Nauta after being informed of the subpoena for security footage. De Oliveira and Nauta scoped out the surveillance area at Mar-a-Lago. De Oliveira then asked a Trump IT employee to delete the security footage. De Oliveira then met with Nauta, then returned to the IT office, and then met again with Nauta. And finally Trump would again call De Oliveira. The indictment lays out the narrative pretty clearly.