After a nimh battery is discharged the voltage will recover/rise back up significantly. If you watch the voltage while discharging you should see it drop lower, but after it finishes it will bounce back up. Generally the resting voltage is not very revealing of anything, it takes a measurement under load to understand the battery condition/charge state. Unless the voltage simply doesn’t recover (junk battery) the voltage reading isn’t of much practical use.

The resistance is a measurement under load, the significantly lower resistance of the new battery is encouraging. Also look for the capacity that the battery provides, the mAh value, this is normally the most important value for a receiver battery, pretty much directly correlates with run time.

The peak sensitivity is for stopping the charge, no impact on the discharge.