I think a somewhat reasonable first-order analysis would look at the fates of similar hard impact failures on the moon and in deep space. The most immediately relevant is the failure of Israel's Beresheet lander, which failed similarly during landing. Beresheet was much smaller and lighter, so the hard impact resulted in total loss of mission. I think the best-case scenario would be a Rosetta-like landing where the craft remains partially operational for a short period of time. The former is most likely the case for Vikram.
In terms of verification, I think rovers are out of the question, as I think China has one of the only active rovers working on the opposite side of the moon - along with any rover having to take on significant risk towards completing their primary mission if they were to try to check this out. It's also taken years for current rovers to move on the order of 10km, so trying to confirm a crash site would likely be impossible.
On the imaging side, the LRO was able to image the location on November 11th, areas of disturbed regolith and debris were identified - at 0.7 m per pixel the largest debris debris was 2x2 pixels, casting a single pixel shadow
Nonetheless, a big congratulations is due to the ISRO for attempting to join an elite club of nations that have soft landed a craft on the moon, and their engineering and design work was sound all the up until the last moments. I hope they won't be discouraged by this (currently uncertain) loss.