Our plane was on time and it took us a good 90-100 mins on ME to get to our resort and another 30-40 mins at check-in. So she'd have time to get to the ADR probably but not to rest if the timing is similar, which it may or may not be. If I were you, I'd make the ADR for later or else do it at a park or at CSR. If you change it to a restaurant in a park, consider that she should allow about 30-40 mins or so to take the bus to the park. The good part about taking a cab is that transportation time is minimal.
Even this is quite good timing. I had a flight that was supposed to land at 4:30pm. I don't recall if it landed exactly on time - but I think it was right around the correct time. At 7:10pm, I was still on the ME bus. It kind of depends on timing.
At teh opposite end, a relative once landed, took ME to room, dropped off bags, and hopped ona park bus - she happened somehow got to the gate about 50 minute after he plane was supposed to land. Not sure how she managed that - except that all the timeing was perfect, and she was the FIRST ME WDW stop. There's quite a difference between being the first ME stop and the third.
Then there's flight delays.
So nap is not a resonable expectation. In fact, she could EASILY miss dinner, if her flight is delayed at all.
Within MCO, you have to take a monorail, and that alone can be somewhat variable. Then you have to wait in several lines for ME - which also can be quite variable.
If her flight is delayed - then the most feasible way to make dinner may well end up being to take a towncar or taxi directly from MCO to Boma.
All that said - if she arrives to AKL ahead of being seated, the lobby is AKL is very relaxing. If you check in for dinner, you can take your beeper up to the lobby and relax on the comfy chairs and couches.
All that said, dinner at the Pepper market is one alternative that could work. I love Boma, so I'd try and make it work. Getting to a park though woudl be complicated. Also, I thikn the new fee thigns changes things. I would not change your current ADR for one that is under the new cc penalty fee system.