Hi there,
Wow, That’s the first time I have heard that. Unfortunately it wouldn’t be the first time seeed engineering may have chosen NOT to bring certain pins, however those are out so , I’m surprised to hear that, I would like a better Explanation from them, a technical one NOT a marketing B.S. either as to why they don’t route through the pin multiplexer? The only other route would be an i/o-expander.
It may be why it’s called a Xiao ESP32S3 in this case the “Sense” version they nurf’d it up.(for the sake of size)
from the wiki, 1x UART, 1x IIC, 1x IIS, 1x SPI, 11x GPIOs (PWM), 9x ADC, 1x User LED,
1x Charge LED ,1x Reset button, 1x Boot button
Hmmm,
HTH
GL 
PJ
I know there are fuses you can burn to change the strapping options and some base firmware functions , but that info is outside my required code base but I would look in that direction if it’s a must have situation. What about the addition of the expansion board to get those 2 IO’s?