The wired article I read about this said only publicly available info was downloaded. Basically they just downloaded all the public tweets. The only thing bad was the photos didnt have the exif data scrubbed and the tweets were in numerical order so it was easy to download everything.
They say Sicknick had texted them Wednesday night to say that while he had been pepper-sprayed, he was in good spirits. The text arrived hours after a mob’s assault on the Capitol had left more than 50 officers injured and five people dead.
“He texted me last night and said, ‘I got pepper-sprayed twice,’ and he was in good shape,” said Ken Sicknick, his brother, as the family drove toward Washington. “Apparently he collapsed in the Capitol and they resuscitated him using CPR.”
https://www.propublica.org/article/officer-brian-sicknick-capitol
Don't speculate if you don't have the goods. His family doesn't want his death politicized. He texted his brother the night of the riot (after it was over) and said the only thing that happened to him was he got pepper sprayed twice.
If you are concerned about tracking and you have an android phone there is an app store called F-Droid. Every app on that store is safe, free and open source and geared towards privacy. From the F-Droid store you can get an app called Classy Shark 3xodus. You can use Classy Shark to scan every app on your phone to see how many trackers are built into each app (a lot!).