HCH-1000 Humidity sensor and AREF

I have a humidity sensor (Honeywell HCH-1000), hooked up as described here. In short: First the capacitor (sensor) is discharged, then charged to a certain percent of full charge (5V). Once the charge times for 0% and 100% are known, the relative humidity can be calculated depending on the time needed to charge. The state of charge is measured through one of the analog pins.

Here is my problem: Other than the humidity sensor, I also have a few temperature sensors (MCP9700-E/TO) using the analog inputs, and I've increased their accuracy by feeding the 3.3V power supply to AREF. Only after a while did I realise that re-scaling the analog inputs from 0-5V to 0-3.3V also effects the readings from the humidity sensor: If it is set to wait until the capacitor gets to 99.3% of full charge, then it trips when the cap charges to 99.3% of 3.3V, not 99.3% of 5V.
I'll add that in my set-up the charge time to 99.3% is 4302 microseconds for 0% RH and 4900 microseconds for 100% RH. Charge time for the open circuit (with the sensor itself removed) is 700 microsecs with 3.3V fed to AREF. But the first time I calibrated was without AREF and then I got 12257 microsec (0% RH) and 27417 microsec (100% RH).

My question is: Should I be worried about the humidity sensor charging only to 3.3V instead of 5V? What could the effect of this be on the sensor's accuracy? Is it possible to have the temp sensor analog inputs scaled a lower AREF voltage while the humidity inputs stay tuned to 5V?

I expect the measurement will be "corrupted "

If you have 2 sensors you could place them side by side one at 3.3V and another at 5V ..

Or do multiple tests short after another - humidity does not change that fast.

What if I used a voltage divider? One resistor between the humidity sensor and the analog input, a second resistor between analog and ground? What resistors would I need so that analog input reads 3.3V when the sensor is charged to 5V.
(Yes, I could just do the math to know the proportions between the two resistors, but I'm a n00b and don't know what order of magnitude they should be.)

I may not be understanding this properly but surely it will take longer to charge the cap to that percentage if the feeding resistance stays the same so in the program adjust the algorithm you presently use to count the time to charge the cap to 99% of 3.3V. Alternatively adjust the resistance down to allow more current to flow , No?