There should be the kernel postinst script /etc/kernel/postinst.d/dietpi-USBridgeSig which installs the driver from Allo. It is however possible that at time of kernel upgrade, Allo did not yet compile the matching new kernel module, in which case the download fails. Please try this:
/etc/kernel/postinst.d/dietpi-USBridgeSig "$(uname -r)"
Ah, latest drivers are indeed missing: http://3.230.113.73:9011/Allocom/USBridgeSig/
Please ask Allo to provide them. Especially the builds for stable RPi kernel releases haven’t been updated for over a year, which is important not only for DietPi users but also for Raspberry Pi OS users, which all have stable kernel packages installed: http://3.230.113.73:9011/Allocom/USBridgeSig/stable_rel/