Hi there!
Thanks so much for the great question! When it comes to digging into your Spam Score, we have a great resource in our Help Hub which breaks down all the factors which go into determining that score. I would definitely recommend checking it out as this may help offer some extra guidance on why your spam score is what it is. You can find that resource here: https://moz.com/help/guides/link-explorer/spam-score
The percentage you’re seeing is indicative of the percentage of sites with similar features to the site you’re researching in Link Explorer which have been penalized by Google. Since the Spam Score metric is based on correlation instead of causation, the solution may not necessarily be to to change factors on your site. There are many different factors which come into play when calculating and assessing Spam Score so this tool is really meant to be used as a way to identify what links you may want to investigate and factors on your site you may want to consider looking into.
As far as next steps to take after having reached out to the site you’re concerned about, I may not be the best person to answer. I’m so sorry about that! I do hope that the info above helps to answer your other questions, though! If you have additional questions about our tools, please feel free to send an email on over to help@moz.com! 

