Margin of Error:
Most likely: SeTi l-l- Adaptive
Less likely: SeTi l--- (or other development)
Unlikely: other high-Se
Video sources: https://www.youtube.com/watch?v=SQSayLl4PFc / https://www.youtube.com/watch?v=eXCRVoz2oss

^ Fe Head Nod + Fe Zygomatic Smile
0:55

^ Fe Warm Swelling + Fe On-Beat Emphasis ... + Pe Body Swaying (P Head Tilt)
0:57

^ Se Presence
Note: He has some Fi-esque resting tension but all of his dynamic movements seem in line with Ti/Fe to me. He also has very symmetrical mouth movements, timed gesticulations and coordination.

Margin of Error:
Most likely: SiFe l--l (l-ll) + Flat Affect
Less likely: NeTi
Unlikely: Other Alpha
Oh dear, we have a complex character here!
Firstly, his baseline development appears to be SiFe l--l as we can see here:

Si:
0:14

^ Pi Fixed Gaze + Si Lightweight Inertia
Si + Ne:
0:36

Pe Body Swaying.. while keeping P Eye-Centricity and Pi Fixed Gaze
He's of the same shade as Leonard Cohen and Mark Kessell, I think.
But in other interviews we also see the presence of Ti! Now I may be wrong here but I think what we are seeing in this interview is SiFe with Ti+Ne conscious:

Ti:
4:48

^ Ji Meticulous Hands + Ji Momentum Halting
Ne+Ti:
0:48

^ Ji Meticulous Hands (Ti Puppeteer Hands) + Pe Bubbling Momentum
And here above we see the full combo of reviser functions... and yet when we look closely we can tell that this combo exists within a confined Conductor vector.. still guided and dominated by Pi's forward gaze/direction. I'd need to take a much deeper look at him to conform, but if so this would be a new development we haven't seen before.
Psychology
Psychologically, we see plenty of Si anecdotal information/trivia, nostalgia, narrativism, etc. But his music style is haunting, in an unusual way. He does very dark cinematic accompaniments to his songs. Perhaps other members know him more and can offer their thoughts on him?
Perhaps not unrelated, he has flat affect:

^ Very clear in photos like this.
If so that's another example of flat affect on an inverted development individual -- further confirming the growing hypothesis that the two have some correlation.

Margin of Error:
Most likely: TeSi l---
Less likely: TeSi of other development
Unlikely: Anything Else
Source: https://www.youtube.com/watch?v=CLhsRSpXE4M
As a CEO of PepsiCo, Indra fits squarely into the Te-lead businesswoman/executive shade. I don't see much margin of error on this one, and she seems to be a pretty standard development. We can see her functions in still shots such as:

And a few GIFs:
0:41

^ Je Head Shake + Je Head Nod (+ Te Plateau Emphasis)
2:09

^ Te Plateau Emphasis + Je Head Nod + ...Fi Excessive Contempt at the end there (right side)

Margin of Error:
Most likely: TiSe ll-l (ll--) Directive
Less likely: Other Beta type
Unlikely: Other Ji-lead
St. Vincent appears to be the same sort of artist as Zoe Saldana & Zella Day and belongs to the shade of TiSe women that includes Taylor Swift and our member Jelle. We can see a very clear Ji-lead vultology in videos such as:

Here she looks like Ji ll-- in development, but I pick this video to start with because we can see the Ji dominance most clearly. Her Se/Ni eyes are seen better in high resolution photos such as:

And we can see her Ti/Fe best in videos such as:

0:17

^ Ti Delicate Pinching + Fe Warm Swelling + Fe On-Beat Emphasis

^ Ji Eyes Disengage Down + J Rigid Posture + Fe Zygomatic Smile.... leading into a Ti Emotional Neutralization (although it doesn't quite get there) And this is also an example of the Stop-Start articulation of Fe/Ti.

Margin of Error:
Most likely: NeTi
Less likely: N/A
Unlikely: Anything Else (SeTi?)
Pewdiepie seems to be a very straightforward NeTi. There is only a very minor signal mixing of Se-esque tautness which is actually just youthfulness from his previous videos. But even then, his eyes-toggles and overall scatteredness (+ tangent-hoppings / parodies) abound. Here is a video of him when he was younger, where the Pe-lead energy is evident:

And we can see the Ne eyes more closely here:

His development seems to change with time, and I think he may be NeTi l-l- at this stage in his life. He is a lot like Jim Carrey in some ways, especially in how he uses himself as a "prop" for entertainment-- exaggerating his reactions in his video game walkthroughs and doing immitations/parodies.
Also, hey he's getting married!

p.s. Totally gives me @puffs vibes.