Not likely.
Rubio has mastered the rapid fire format of these pseudo debates and left Cruz bleeding in the alley last time.
All the candidates and the mods will now dial in on Cruz.
I don't believe Fox will go out of their way to highlight Trump's absence and may be precluded from doing so by RNC rules.
They will likely hold the debate as if Trump never existed.
This format is nothing like a real collegiate debate and Cruz has shown he is far to long-winded and circumspect to compete effectively.
Rhetorical flourish and detailed, verbose responses do not serve him well. It's like bringing a Dr. Seuss book to a dog fight.
Ouch. LOL. Trump might show up 5 minutes before it starts. Depends on the polling.