Insert after paragraph before another plugin’s output

Hi. I’m using Ad Inserter (great work!) to insert a variety of text on my site. I’m now trying to use it to insert a sharing badge AFTER the closing text of each post, but before the navigation display provided by another plugin. If I use “after content” the text ends up after the navigation display. I’ve been trying to use the “after paragraph” function but so far no luck. I’ve tried specifying as the last paragraph, or matching on the text that always appears at the end of each post. But no matter what combo I try, nothing appears at all in these cases. Any clues? Thanks!