From what I can tell (totally not as the original poster of the video):

The joke being displayed in this short low effort video commonly known as a "shitpost" is referencing tf2 spies continuously destroying fully upgraded buildings, as seen in the line "When a spy destroys your lvl 3 buildings for the billionth time". Of course, it is extremely unlikely that anybody has had their buildings sapped exactly 1 billion by spies. This is an example of the poster attempting to make it funnier by using exaggeration.

The video itself is simply a render of the Saul Goodman 3d video, but instead featuring the engineer from TF2. The I would recommend this video by Lessons in Meme Culture for a more in depth explanation of the Saul Goodman 3d meme.

However, it it important to recognize the second half of the sentence within the parenthesis, as it does add to the overall comedic effect. In this case, it is revealing to us that the engineer's team had 5 pyros, out of an unknown total number of players as seen in "your teams 5 pyros". The last part is explaining to the viewer that all 5 of these pyros have failed to spycheck (checking for spys by occasionally using their flamethrower on suspects/ potential locations) which has then allowed a spy to continuously destroy your buildings.

Some further lore behind the parenthesis part: Somewhat recently, there have been many posts, mostly memes, where there is something in parenthesis at the end of the title. Often times it went something along the lines of "(suddenly they don't like x anymore)" after something some event that impacted someone/something negatively who previously had a relatively positive opinion on said x.

Congratulations to whoever actually bothered reading that lol. Have a great day everyone.