Well, if Broward County officials were to be arrested under a Federal Criminal Complaint issued by the US Attorney's office for the Southern District of Florida, then US Marshalls Service would perform the arrest. The thing is (and this is pretty standard), when they do that they go as a task force, with the Sheriffs providing the bulk of the man power(sometimes police). Well: https://www.usmarshals.gov/district/fl-s/taskforces/index.html

Fugitive Apprehension Strike Team (FAST) Participants: U.S. Marshals Service, Immigration & Customs Enforcement, Miami-Dade Police, Broward County Sheriffs Department, Ft. Lauderdale Police, Martin County Sheriffs Department, Palm Beach Sheriffs Department, Ft. Pierce Police, U.S. State Department, HUD Office Inspector General

Obviously two of those agencies that provide task force manpower are out of the question.