There are a few people on the site who are good with Trump, but I believe they typically avoid offering opinions on these abbreviated contemporary signatures. They are difficult authenticate reliably.
+1. The chance of Trump signing a Hillary photo/cover are astronomically slim and the chance that random seismograph graph writing is Trump's is even slimmer, IMO.
Like at first, the seemingly too many 'm's in a Jimmie Foxx signature, Trump's autograph does have a logic, a usual set number of peaks, shape, and overall vibe to it that this sorely lacks.
This feels like somebody writing this that didn't before that day, with very little practice and forgery skill, if any at all.
While I agree with your assessment of the autograph, I don’t think he’s too particular about what he signs. And I think he’d rather enjoy writing over Hillary‘s face. LOL