So they had enough evidence for a search warrant but not an arrest warrant.
And they need a SWAT style search for someone they didn't even have enough evidence to arrest?
The probable cause used for the search warrant is not the same as the probable cause for an arrest warrant. Essentially, the affidavit necessary for a search warrant needs to show probable cause that a crime has been committed and the place to be searched is likely to contain evidence of the crime.
For an arrest warrant there needs to be a showing of probable cause that a crime was committed and the person to be arrested committed the crime
I found a copy of the search warrant on the internet, but the internet copy did not include the affidavit in support of the warrant.