The SOC is only a reported parameter, it does not control the charging. Charging is based on battery voltage. Absorption only restarts if the voltage falls below float, about 0.1V below for lithium from memory.
Also, have you adjusted the Multiplus settings to the battery voltages recommend by the manufacturer as the default voltages for lithium are based on Victron batteries and are lower.
Your shunt settings are fine which is one common cause of poor accuracy. The other is incorrect wiring on the shunt. See the attached FAQ. If not wired right, especially the chassis ground in a vehicle you can get odd results.