IOTL, after the assassination of Drusus, the Italians planned to launch their revolt the following spring, so as to take advantage of the winter to prepare. As it happened, Caepio caught wind up something being up in Asculum, and the inhabitants there, fearing the game was up, killed him and other Romans in the city on the spot, launching the war before the Italians were fully prepared. The result of this was the Marsi, merely 100 miles from Rome, were unprepared to immediately march on the unprepared city as they had planned to in the spring. Other Italian tribes such as the samnites also took awhile to mobilize for the early start to the war. This provided the Romans crucial time, which was probably decisive in keeping the Etruscans and Umbrian cities on Romes side.
So what if Caepio does not catch wind of hostages being exchanged in Asculum, and the Italians are able to wait until the spring to revolt against the unprepared Romans? If the marsi are able to march right up to the gates of Rome, might the Romans capitulate right there, or risk Rome being sacked?