As it is a pt1000 sensor are you using a 2 wire or a 4 wire connection? With 2 wire you will need to cal out lead resistance or accept the temperature error, and for 4 wire you will need 2 switches per channel and buffer them both after the switch to feed the ADC. Best is to arrange any gain setting and filtering on the buffer stage as well, a low pass filter at the input to the amplifier will help, but remember the settling time for the filter after changing inputs to avoid reading the step change as an error.
Use the switches from the same 4067 to switch the wiring from a single sensor, otherwise you will have errors from temperature differences between the IC's affecting readings. Buffer after the IC because the ADC input current will cause issues if you feed the input current through the poorly defined switch resistance. Low pasx filter because temperature is a slow signal. You might also want a low pass filter on each input to the switches, or at least a series resistor for ESD protection, and sample after a delay for settling, or use a series of readings till they settle to a value.