Hi FroggyC,
I don’t believe that disabling likes for a specific post is possible. I’ve found this data explorer plugin query (provided you have the plugin) Users who like flagged posts. This allows you to see what users are liking flagged posts.
Another suggestion, if you no longer want any replies on the topic to be posted but for it to remain visible would be to archive the entire topic. This however, disable likes on all posts.
Personally, if people kept liking inappropriate posts I’d be looking at the moderator guide and issuing warning or suspensions.