It's probably better than most charts out there but that's not saying a whole lot since the best data out there for the vast majority of that location is ETOPO. The chart is kind of worthless inside of 100 meters but will be decent for showing dramatic drop offs. It also looks fairly accurate (given the low resolution) compared to the different data sources I've seen.

In this case, any interpolation you do on this chart won't add a lot to the chart and will be extremely inaccurate around the reef. It's probably best to do a direct conversion with the IMC or recalculate the data with their source data for this project.