Lethal Danger by Jerusha Agen

This K-9 team is trained to eliminate threats. This threat could eliminate them.
Being a loner is getting old. Jazz Lamont still can’t fit in at the Phoenix K-9 Agency, and she’s losing her best friend. At least providing security with her K-9 partner at the Tri-City Fair will mean revisiting the only place where she once belonged. But a series of accidents threatens her beloved fair and puts lives at risk.
Thriller author Hawthorne Emerson suspects foul play after the first “accident.” Moonlighting as fair security to investigate the death of his sister’s boyfriend, he’s eager to find the truth. He doesn’t expect the task to lead him to the cult he escaped.
Finding the culprit behind the sabotage is personal for Jazz and Hawthorne. But someone else has a personal stake, too. Someone who wants Jazz dead. When everything she thought was true is dismantled, can Jazz risk trusting others—including God—to survive?
Lethal Danger continues the thrilling story of the elite Phoenix K-9 Security and Detection Agency that began with Hidden Danger (Guardians Unleashed, #1). (Each book can stand alone or be read as series installments.)