Partial answer: (Including final solution)

The two TV screens that get linked at some point show a baseball field and Baby Bear. The logical conclusion is that we're dealing with the Cubs.

We can then narrow down Deusovi's list to two suspects:

Kyle (aka Charles) Hendricks, age 26 (pitcher for the Chicago Cubs)
Jon (aka Casper) Lester, age 29 (pitcher for the Chicago Cubs)

As for which one, it has to have something to do with

the numbers from the sudoku puzzle

But i cannot figure out what.

Dark then light. They come in pairs. The first number of the pair is the line number; the second is the letter number.

If we use this on the news article in the first image, this gives us:

thbrtyfoe

From the hint we know

Also, I made a mistake - foe should be for.

And there appears to be another error, so in the end we get

thirtyfo[u]r

Which is

Jon Lester's uniform number.

So the culprit is:

Jon (aka Casper) Lester, #34, age 29 (pitcher for the Chicago Cubs)

Partial answer: (Including final solution)

The two TV screens that get linked at some point show a baseball field and Baby Bear. The logical conclusion is that we're dealing with the Cubs.

We can then narrow down Deusovi's list to two suspects:

Kyle (aka Charles) Hendricks, age 26 (pitcher for the Chicago Cubs)
Jon (aka Casper) Lester, age 29 (pitcher for the Chicago Cubs)

As for which one, it has to have something to do with

the numbers from the sudoku puzzle

But i cannot figure out what.

Dark then light. They come in pairs. The first number of the pair is the line number; the second is the letter number.

If we use this on the news article in the first image, this gives us:

thbrtyfoe

From the hint we know

Also, I made a mistake - foe should be for.

And there appears to be another error, so in the end we get

thirtyfo[u]r

Which is

Jon Lester's uniform number.

So the culprit is:

Jon (aka Casper) Lester, #34, age 29 (pitcher for the Chicago Cubs)

Partial answer:

The two TV screens that get linked at some point show a baseball field and Baby Bear. The logical conclusion is that we're dealing with the Cubs.

We can then narrow down Deusovi's list to two suspects:

Kyle (aka Charles) Hendricks, age 26 (pitcher for the Chicago Cubs)
Jon (aka Casper) Lester, age 29 (pitcher for the Chicago Cubs)

As for which one, it has to have something to do with

the numbers from the sudoku puzzle

But i cannot figure out what.

Partial answer: (Including final solution)

The two TV screens that get linked at some point show a baseball field and Baby Bear. The logical conclusion is that we're dealing with the Cubs.

We can then narrow down Deusovi's list to two suspects:

Kyle (aka Charles) Hendricks, age 26 (pitcher for the Chicago Cubs)
Jon (aka Casper) Lester, age 29 (pitcher for the Chicago Cubs)

As for which one, it has to have something to do with

the numbers from the sudoku puzzle

But i cannot figure out what.

Dark then light. They come in pairs. The first number of the pair is the line number; the second is the letter number.

If we use this on the news article in the first image, this gives us:

thbrtyfoe

From the hint we know

Also, I made a mistake - foe should be for.

And there appears to be another error, so in the end we get

thirtyfo[u]r

Which is

Jon Lester's uniform number.

So the culprit is:

Jon (aka Casper) Lester, #34, age 29 (pitcher for the Chicago Cubs)