Hi Peter,
Can you please confirm if your SDA/SCL waveforms correspond with data transfer waveforms provided in the datasheet? (DIY8883 - under data transfer)
You might have to possibly debug if there are inconsistencies. This will help me in understanding why its not working on your end and possible replicate the issue once I get the parts on hand.
In your first post, you noted the EVB of this part too. Are you using the GUI for the evaluation board as well?
Regards,
Nouman