Does every 100 million views mean another certification added to the record?

No. The views have to come from the U.S.
100 million US views = 1,000,000 U.S. sales

Okay, because I was wondering why Drunk In Love is still certified platinum with over 200 million views on youtube.

Well it was a local semi-hit so most of those views probably came from the USA.
It's just a matter of her label paying RIAA for the certification so they're probably holding off to make it seem like a bigger hit.
Like RIAA hasn't certified Wrecking Ball yet. I'm guessing RCA is waiting for it to gain more views + sales so they can pay for that Diamond certification.

How much does that cost?

How is Justin Bieber's Baby certified Diamond tho? The song sold 3.5M and I'm pretty sure that 650,000,000 of its 1.1 billion views don't come from the US

! and there's no way 500M views out of 600M for Bad Romance are from the US

Those are the rules. Clearly Bieber is global and Gaga is local.
I do believe that 650M of Baby's views come from the U.S. the video was huge.
Idk about Gaga maybe she paid RIAA for the diamond award just like she paid Billboard to include Dope's performance views to its streams that week to push it to top 10. She probably wanted to be the first female artist to get a diamond award just so she can tweet "I guess diamond awards are a thing now" later on when other gorls get it.

EXPOSE a bit