It would be a contradiction if this was the mirror universe, where people rise in rank upon the death of another. But that isn't necessarily the case here. Even if the second officer died before waking, Picard would only be the ship's captain until they reached a Starfleet base. At that point, Starfleet would assess the situation, including the captaincy. They could very well say, "Well done, my boy!" and leave Picard in command, or they could simply pin a medal on his chest, add the Picard Maneuver to the history books, and assign a new captain awaiting a command to the ship. Apparently, the latter happened (that or the original XO came out of his coma and assumed command at a later date).
I've read MJF's The Valiant and the first three Stargazer novels. I can't see how Picard could have served as an XO somewhere else before his stint as Stargazer's second officer, as he didn't have enough time; he became the Captain at 27. The suggestion that Picard may have served on some ship where he wasn't doing what he trained for, but was still an XO seems to be out character for him. He was always portrayed as something of a top notch officer and a very promising cadet. He wouldn't be relogated to low level duty. He never seemed like someone who only wanted the rank. He wanted to explore...although he did allude to some incident at the academy when he was talking to Boothby in First Duty...
The Stargazer series is filled with things that suggest a lot of people at first didnt think Picard should be in command. That one admiral(i forget his name) was always trying to find things to get Picard out of command. It was kinda like an 80s cartoon show where the bad guy is always trying to win and the good guy seems to slip through everytime. I wish they would continue though cause i was hooked on them when they were all out, but they just sorta ended. I was sad they didnt even get to jack Crusher!
I believe the last part of the "Double Helix" series that ran through the TNG books (IIRC, #51-56?), was a tale aboard the Stargazer and Jack Crusher has a role in it. Hopefully Pocket Books and MJF get together and do a few more books somewhere down the line...
hopefully so, i was so into this series when it came out, i think i re-read them at least 2-3 times. The Buried Age was a great look at the final mission, so how about someone pick up the pieces( i know that there is still a lot of ground to cover) and have some great Stargazer stories!