On the software side I’m not sure you would need to change anything; USB is self-discovered and the USB switch on DB410c uses a seperate IC so nothing much should need changing.
Likewise its, on the hardware side it is safe because DB410C does not connect anything to pins 8 and 9 (where the new D-/D+ signals are) so there’s no electrical risk.
However, I can’t really see how this can work mechanically. The hub is in a QFN-36 package were the N stands for no-leads. Have you got a clever idea regarding to gain physical access to the extra USB port?