PMIC with Li-ion charger, stable output and USB OTG?
From having a look on Digikey I found the following Texas Instruments part that seems to fit your needs. I found this component by looking in the PMIC(Battery Chargers) section of the Digikey search.

BQ24090DGQR

https://www.digikey.com/product-detail/en/texas-instruments/BQ24090DGQR/296-38875-6-ND/5143531

http://www.ti.com/lit/ds/symlink/bq24092.pdf

(Couldn't leave this as a comment as I don't have enough reputation, sorry.)