No matter what, Trump gets blamed. To this day, it is Perot's fault that GHWB didn't get traction. The party NEVER owns its mistakes.
For one thing, Perot ran as an independent candidate, not a GOP
candidate.
For another, there would not have been a Perot had Bush not ignored
the grassroots or broke his promise, “read my lips, no new taxes” but
passed new taxes.
If Trump is leading by a good margin of delegates at the convention
and gets screwed, the nominee will be ill-legitimate in the eyes of
American voters.