There are several sets of secret collectibles in Directive 8020, one of which are the Simms Recordings that are scattered across episodes and areas. While not missable since you can always replay to get them, they do tend to be placed in out of the way locations.
This guide for Directive 8020 lists the locations of 10 of the Simms Recording secret collectibles by episode, checkpoint, and room.
Green Tea
Episode 1: Little Star
Crew Quarters
Quarters -> Monitoring Crew -> Side room on the left
Inside the room, look to the right of the entryway for a wall monitor with the video recording.
Patches
Episode 1: Little Star
Medical
Storage -> Lift lockdown -> Medical Reception
Proceed up the stairs for another monitor with a video recording.
Red Alert
Episode 2: Best Laid Plans
Ship Shape
Head up the right side stairs to find a wall monitor with a Simms recording.
Sweet Dreams
Episode 2: Best Laid Plans
Sleuth
Crew Complex -> Locker Room
Step into the locker room and find the wall monitor on the left side with a Simms recording.
Slingshot
Episode 3: The Sample
Gear Up
Hub -> Tool Storage
Inside the Tool Storage room, head left to find another monitor with a Simms recording.
Special Permission
Episode 3: The Sample
Search
Mess Lobby
Descend the stairs and hook left to find a wall monitor with yet another Simms recording.
Hostile Fire
Episode 5: Mr. Williams
Radio Silence
Bridge Ops -> Scan -> Storage
Before entering the Airlock, bear left and over the obstructions to power up Storage. Once inside, the monitor with the Simms recording should be on the far side wall of the room.
Field Agent
Episode 6: Hostile Takeover
Detour
Exec Office
Access the Exec Office and check the left side of the far wall for a wall monitor mounted in the corner.
Rabbit Hole
Episode 8: Come True
Redirect
Deck 2 Locker Room
While sneaking past the creature, power up the Deck 2 Locker Room and then access it to find a monitor on the left side.
At Peace
Episode 8: Come True
The Way Back
After powering up an alternate Server Control Panel for the second time, crouch and crawl through the organic obstructions to some server racks. Lower them to find the final wall monitor and its Simms recording in a room to the left.
Those are the locations of all 10 of the secret Simms Recording collectibles to be found in Directive 8020.