The Sealife DC2000 should be using DNG RAW format which is the Adobe format. Adobe makes Lightroom, Elements and Photoshop CC which I knew as the old CS. I have tried using the old CS but there is a lot to it and a big learning curve. I don't edit enough to justify the time to use it as intended.
Since the DNG format is the same and that I use Adobe Photoshop Elements, I will key on Adobe. There are other editors but you may/will have to convert the format from DNG to the application RAW format. The converters are generally free but I can't tell you about the quality of them.
CC is the full blown editing application. It can do a whole lot more than just photographs. More expensive too.
Elements is in between CC and Lightroom. I use this for RAW and jpeg photo editing but has less features than CC. The user interface is a selling feature.
Lightroom, which I don't use, seems to be popular but also may be more difficult to fully use as I understand. People who use it should comment here I would think.
There can be quite alot to all these applications which may make it difficult if you don't want to spend the time.
You can get a better comparison here -
Lightroom vs Photoshop Elements. It is from 2016 I think so some things may have changed.
You can try some free applications. There is a list on
Best free photo editing software. I used Picasa in the past but I think they are forcing everyone to the Google cloud. I wanted local PC based. I liked the printer GUI. I don't know what it looks like now.
On the other hand you may get what you pay for and if free and in their cloud, who knows what they will do with your images and your email address - marketing, data mining, popups, something?
You can google "best raw photo editing software" which will give you a bunch of answers. You can also try
UnderwaterPhotography.com | #1 Since 1996 forums, wetpixel.com and DPreview for answers. I can only tell you about photoshop. I edit RAW and if you wish you can check my gallery on SB to judge if that is what you want to do.
You may want an application that can adjust white balance in the RAW photos if you are not taking care of that underwater or shooting auto white balance.
So bottom line is that you can edit RAW format with any application as long as the format is right.