They probably didn't and just got the feature for free due to the chipset they were using.
It's been hypothesised elsewhere that the H1-D is far more software based than H2-4D. If that is true and they are doing Dante in software then they are limited to 96k anyway on the output side.
These boxes are primarily designed for QA of encoded Atmos in studios. Almost all Atmos is at 48k it's possible to do 96K but it halves the possible object count so almost nobody does.
I can tell you for free that in the target market absolutely nobody cares about 8 channel 192k LPCM.
There are a few people who care about high bitrate multichannel playback but that crowd want DSD256 which you aren't going to get that down HDMI audio.
On the content creation side that is done with boxes from Merging Technologies and on the playback side with a select few multichannel USB DACs.
