Different branches of paganism deal very differently with UPG or unverified personal gnosis. Some feel it's inappropriate, some see it as inviolate, some fall in the middle. Where does fictional reconstruction fit in there? You might assume that it UPG would be highly valued in fictional recon, and you'd be correct, but perhaps not for the reasons you'd think.
In the sorts of fannish circle that generate fan fiction and meta, people will post their headcanons: their own personal interpretations above and beyond what's giving in the canon. Some of these are quite straightforward, while some are complex and turn brief moments in hundred-thouand word epics. The connection to UPG is obvious, but the most interesting thing about headcanons is that they are not considered mutually exclusive. It's expected that you can have your own headcanon while appreciating the differing ones of other people; some people have multiple versions of headcanons of their own.
For the fictional recon, it is not accidental that 'canon' is also a religious term. However, while there are still ship wars and arguments over how canon various information is, in most fandom circles, the norm is to appreciate the variety of headcanons available. This is an attitude that would serve more pagans, in my opinion. By treating UPG as headcanon, a fictional reconstructionist has the opportunity to appreciate a diversity of interpretation and to see his or her gods from new angles - even the non-fictional ones. Whether you agree with the headcanon is ultimately secondary to whether or not it prompts a good story.
To use a modern example, Phil Coulson's death was widely ignored by fandom - at first people wrote stories explaining how he was alive, and not long afterward it was essentially decided by fandom that it wasn't even necessary to explain it in any given fic. It was just a given that Fury had faked his death, and eventually Agents of S.H.I.E.L.D. made that fanon (SPG) into canon. While this made telling stories with Coulson in them easier, in some ways it limited what fandom could do because writing a dead!Coulson fic was harder, even though Coulson's death was apparently canon for months.
If you can't quite bring yourself to conflate your canons, perhaps you'd be more comfortable with another "H" term: hypothesis. Some pagans would benefit from treating their UPG as a hypothesis: something that needs to be tested, refined, and evaluated. If you similarly view the UPG of others as hypotheses, you can seek any useful ideas or possible truth in even UPG that conflicts with your own experience. Whether or not you ultimately decide that two pieces of UPG are or are not compatible, the time spent gives a greater understanding of your own experiences and knowledge because they have been compared and even challenged.