I don't think you could compare Sonadia Island port with Kyaukphyu in Myanmar or Gwadar in Pakistan.
For Pakistan and Myanmar, those ports are not vital for their foreign trade especially container trade and not an urgent need.
Sonadia however is.
The placement of Sonadia is along the Export zone corridor in Bangladesh (at the end of it).
Mongla is out of the question and too far inland as a container port, Payra is going to be more of a military marine/SAR naval port (50/50) and has draft issues and Chittagong is already saturated (and having draft issues) as far as container handling capacity (even with the addition of new mooring terminal).
Sonadia was and remains our only hope for a large deep-draft container port. If the Chinese want 70~80% stake in it, sorry but no can do. We can pay a few dollars extra and have someone without hegemonic ambitions build that port.
Like the Chinese, we have to look at our own selfish interests as well.
But I think the Chinese will be happy with Kyaukphyu port without the Rohingya.
That is one of the major reasons IMHO why Rohingya were kicked out of Rakhine in the first place.
The Chinese don't want to risk having a Rohingya population in that area who possess a backbone and an independent mindset to cause disruption in that port and the oil pipeline. Too much trouble in Chinese hands to handle...so Rohingya had to pay a price and they had to go.