A Nottingham Q wildcard is quite likely. But that's a given, isn't it? If it's a MD WC, she's have had time to play Sharm and get back in pretty much plenty of time.
Can't believe it's coaching commitments or she'd have known about them before - after all, it's only two/three days away, unlikely to suddenly have 'forgotten' one or something to come out of the blue. The ranking is still a little way off - she's only got two counters now so it'd've made sense to stay the extra week if a ranking was her main goal.
Yes, I can't imagine that this is anything to do with any short term ranking aims, especially as Naomi would have to win the title this week to get a ranking. At the very least, certainly not an expectation.
I think short term ranking aims and defenses are often overegged on this forum, anyway. I would hope most players look into the bigger picture rather more than is sometimes suggested.
Assuming Naomi is making a comeback (and I can't imagine she'd be travelling to professional tournaments if she were not), I would expect her to start quite gradually and avoid the temptation to go flat out week after week to ensure that she re-adjusts to the lifestyle in both body and mind. It may be that having seen the players in Egypt she thinks she is in with a good chance of going deep this week and would prefer to rest / train next week.
incidentally, she is still shown on the JTC website as a coach.