Trump has to get the vote to be the Republican nominee to run for President. If he doesn't and DeSantis does, but Trump runs as an Independent....WTF do you do? Pick DeSantis and prove the establishment right, pick Trump and possibly divide the Republican vote?
Either way, win for the Democrats...
I just don't believe it will come to that. Just look to Trump if it does. He'll advise you what to do. He doesn't want to see the vote split either, for the same reasons as you. If it came down to it and it was an actual scenario and the threat of splitting the vote did exist, I think he'd bow out. He loves the country too much to just give it to the dems.