Multi-cell LiFePO4 charger ICs
Turns out I just wasn't looking in the right places.

Here's a list of multicell chargers specifically designed for LiFePO4 that are available from Digikey: https://www.digikey.com/short/p4ttc0

And here's a list of multi-chemistry chargers many of which will support LiFePO4 (unfortunately it's not possible to automatically filter out the ones that don't) https://www.digikey.com/short/p4tttb