Yes, you can use 34.4064 MHz.
Previously, we mistakenly stated 33.33 MHz. We have characterized and confirm we can run up to 35 MHz, as stated in the datasheet. PSoC Creator does not reflect that yet. But you can use the PDL to set ECO frequency with PSoC Creator.
The USB requires 0.25% clock accuracy. The I2S does not require any, but it is recommend to drive the audio subsystem from PLL.
There are many techniques to sync the USB and I2S clocks. This code example implements one:
If you don't sync the I2S and USB clocks, doesn't matter how accurate they are, you eventually would see some artifacts.
Thank you very much for your very fast answer!