I have always maintained that Nick's $100,000 bail was very high for FTR, though legally allowable. Most FTR's are bonded at $10,000 or OR for offenders who haven't actively tried to evade registration, and even for those who have tried to evade it, it's rarely higher than $25,000. I've seen one instance of $50,000, but that was only because they suspected the RSO of another crime when they arrested him for FTR.
A $100,000 bond definitely means they want Nick in custody. They know he can't scrape up 10 grand for the 10%, and since Nick doesn't appear to have any other charges or warrants, only one reason to keep him locked up: He is the prime, if not only, suspect in the disappearance, and potential murder, of Kelli.