Ok if the light labeled 'moca' is on, that's a plus.
This might fall into the "duh, of course I did" category but did you try rebooting the modem and Tivos afterwards?
Do you know where the TV splitters are in your home? If you can find them, they're labeled with a frequency on them. You'll want splitters that are rated for at least 1000 MHz (1GHz) but ideally higher. (If they're old or don't happen to be sufficient, they're easily replaced and only cost $3ish for proper ones.)