First and foremost, there are multiple SPaG errors that need to be fixed.
Second, the overall piece is lacking in clinical tone. Here's an essay by 
A Random Day that might help a bit with getting the tone on track.
Special Containment Procedures: SCP-XXXX in uncontainable with the Foundation’s current resources.
Consider: "SCP-XXXX is currently uncontainable without prohibitive expenditure of Foundation resources.
This is containable, it'd just be really expensive.
There is to be constant surveillance of the Hudson Valley region for sightings of SCP-XXXX via CCTV surveillance.
Consider: Foundation-accessible visible recording devices in the Hudson River Valley region should be continuously trawled by Foundation AI for anything that matches SCP-XXXX's description.
or something like that.
Once SCP-XXXX is spotted and one of the family members doesn't believe it's story the corresponding Mobile Task Force is to be sent.
How are we to know if the family doesn't believe the story? All appearances of SCP- should trigger a response.
Description: SCP-XXXX is a white middle-aged male with a large mustache dawning a police uniform.
I don't know what "dawning a police uniform" means.
SCP-XXXX reportedly drives around in a police issued Dodge Charger with a license plate of ████████. The only available descriptions of SCP-XXXX are from eyewitness accounts of those affected by it.
Tone. Revise. Also, if you're constantly looking for it via cameras, there should be footage. Unless the footage gets anomalously deleted, which you should clarify.
SCP-XXXX targets family residences where at least one family member is absent from the household.
Tone. The entire paragraph is clear, but should be edited for tone.
Once questions are finished SCP-XXXX will tell the family that if they have any more questions to come to the police station and excuse himself.
Same.
The family tend to never ask any more questions and will proceed with their lives after holding a funeral for the deceased loved one despite not having an actual body.
Same. Also, this is just awkwardly phrased. It is also unclear what the Foundation originally believed happened to the bodies.
Addendum 1:
Protocol-XXXX
The protocol is also not written in a clear, clinical tone. I realize that it is merely a vehicle for the intrusion event, but it still needs to match the clinical tone.
-DISPLAYING MESSAGE
He's coming for you next. If you're reading this then for the love of Gs̄̾͒҉̪̫
This is great. Also, I think this is where you should probably end it.
Section it off into an addendum that says something along the lines of:
"On March 3rd, 2018, an intrusion into SCiPnet was detected and traced to this particular entry. It appears that whatever the intrusion was, it was attempting to modify the article to include the previously indicated text."
Then say that the Foundation acted upon the intelligence and were unable to confirm the veracity of the claim, nor were they able to confirm the existence of Dr Whatever.
I would remove the article revision and the interviews. They add little to the story, and the dialogue isn't clear.
Maybe add something along the lines of
"Over the course of several days, multiple intrusions into the network were detected, with shorter and shorter versions of the original message left behind.
Since <date>, no further messages have been received."
Give it a nice mysterious ending.
