I'm not very experienced in reviewing Idealscope or ASET images, so I don't really know what to look for. I'd appreciate any feedback that you can offer regarding the attached images. Thanks in advance!
The images are positive in terms of performance. No way to know how visible the inclusions are. They can show in reflector images (like these) more than in ordinary mag photos. For that matter these photos are very large, and if the diamond is a normal size I’d expect that off-center crystal group to be pretty negligible.
As already stated, it can be misleading to try to use light performance imaging to get a handle on clarity issues. It would be better to have an actual frontal image or video of the diamond. An accurate description from the vendor can also ease your concerns, and of course, nothing better than seeing it for yourself.
Having said all that, it does appear to have a dark crystal under the table, and I get the sense that it may be near the surface. It therefore might be visible to the naked eye. Alot depends on the overall size of the stone. If this is a 2ct it's more likely to be able to see that crystal. If it's a half carat, not so likely.