The leads/cables to the various power supplies, batteries and loads have resistance. The current meters also have series resistance. The charger dynamically reduces charge current depending on the voltage sensed at its VBUS pin (using the VINDPM feature), BAT pin (as part of normal termination) and TS pin (through its battery temperature monitoring feature via battery thermistor). Therefore, you must use voltmeters to measure the voltage as close to the IC pins as possible instead of relying on the power supply's digital readouts. If a battery thermistor is not available, either disable the TS function or replace with an appropriately sized (typically) 10 kΩ resistor.
When using a sourcemeter that can source and sink current as your battery simulator, it is highly recommended to add a large (1000 µF+) capacitor at the EVM BAT and GND connectors in order to prevent oscillations at the BAT pin due to mismatched impedances of the charger output and sourcemeter input within their respective regulation loop bandwidths. Configuring the sourcemeter for 4-wire sensing eliminates the need for a separate voltmeter to measure the voltage at the BAT pin. When using 4-wire sensing, always ensure that the sensing leads are connected in order to prevent accidental overvoltage by the power leads.
For precise measurements of charge current and battery regulation near termination, the current meter in series with the battery or battery simulator should not be set to auto-range and may need be removed entirely. An alternate method for measuring charge current is to either use an oscilloscope with hall effect current probe or place a 1% or better, thermally capable (for example, 0.010 Ω in 1210 or larger footprint) resistor in series between the BAT pin and battery and measure the voltage across that resistor.