quepasabebe says that an undercover police grabbed the phone from the suspect while it was unlocked.
With a lot of high-security systems with forensic tool resistance or even anti-forensic features, investigators will adapt and make different procedures if they expect you are using something of the sort. While you should expect companies who sell exploits for mobiles like digital forensics companies likely have Pixels or GrapheneOS on their sights, in most cases you shouldn't expect them to take the same process as an ordinary smartphone with stock Android. While there is no evidence there is an exploit of a supported new Pixel with GrapheneOS, you should expect the procedure to be different even if there was one - since the users of the OS would be inclined to behave very differently compared to ordinary people or unqualified criminals with lackluster knowledge in computer security or digital forensics.
Police are likely to expect GrapheneOS to be trouble, so them going to attempt to seize the phone just to acquire evidence it through a toolkit like Cellebrite is likely out of the question. They'd likely conduct surveillance on the suspect to acquire the phone while it is unlocked or to discover the PIN/password as mentioned in this example. Doing this allows them to turn off unlock methods and enable USB debugging to perform basic extractions and display capture. For cases where they think plugging the device in would trigger a kill switch, they have dedicated cameras to take pictures of the screen without connecting it to anything. Devices would also be placed in faraday cages or in any other signals blocking setup to prevent remote erasure.
If any device is completely unlocked and with the security measures turned off then any extraction tool would work. You shouldn't expect this 'TekPro' to be special to other tools, mobile forensics toolkits are often chosen out of investigator preference unless another is needed for a certain device or app. You'll find investigators use a variety like Cellebrite Physical Analyser, Oxygen Forensics, Magnet AXIOM etc. to perform their evidence processing. Cellebrite is a gold standard since they do both evidence acquisition (UFED) and processing (Physical Analyser, Investigator, etc.)
When relying on digital forensics questions on this forum you need to constantly remind yourself many information is speculative as companies try their best to black box their systems and not disclose unique capabilities that their enhanced plans for law enforcement and government may have. I also personally have my doubts they'd even mention if they had any unique capabilities with GrapheneOS devices in public, considering how many of their users sleuth around the Internet and are interested in anti-forensics. Having any sort of knowledge like that in public would be a tip-off and probably cause users to suggest more anti-forensics.
Also @quepasabebe The file you sent has an invalid URL, would you be kind to upload it again? I would love to read this report. It would be the first report I've seen with GrapheneOS in the wild that has been public.
