As Tim pointed out, he can't show you what's in the review queue due to the sensitivity of the data. But, below is a snip of the St. Mary's County filter, where I live, showing you what drives eBird.
When you have a flagged submission, it's for one of two reasons, both regarding exceeding a threshold value. First, a high number that exceeds the non-zero threshold in the filter. In this case, let's use Snow Goose as an example. You find 6 Snow Geese in St. Mary's which is above the highest threshold of 5. That's a great number as they're not that common down here but not a mega. If you put in some details that say why it was a SNGO and not a Ross's or a Tundra Swan, or a white domestic goose, that should be enough for it to get validated when a reviewer sees it.
Second scenario, again because it exceeds the threshold value, but in this case something rare like Ross's Goose with a filter value of Zero 365 days a year. Mikey Lutmerding found two ROGOs at the end of Harry James Road several years ago that is the only record of ROGO in St. Mary's. In this case, because they're so uncommon, photos would be really great and almost mandatory since SNGO and ROGO can look very similar especially at a distance.
Most eBird users in Maryland understand the status and distribution of birds throughout the state well enough to know when something is going to be a Zero/365 bird and will strive to document it well enough to be validated right away. In some cases where it's not possible to get documentation shots, and it's a statewide or regional records committee review species, the eBird reviewers will punt the submission to the RC. Birding by committee sucks but sometimes it's out of our hands. The Loch Raven Western/Clark's Grebes and the two Western-type flycatchers in Frederick and Baltimore Counties are recent examples that despite lots of high quality photos, eBird reviewers can't determine the species.
Each county has a filter specific to it. The numbers may be similar or they may vary considerably. But, the filters are what drives eBird and it's not something that most people know of or understand. As Tim said earlier, the reviewers try and treat everyone equally. If you have provided adequate details about why your bird is what you claim it is, or if you have photos/video/audio that is conclusive, it's usually just a matter of time between your checklist submission and when a reviewer validates it. Remember that the reviewers don't get paid, they're also birders, and they don't sit at their respective computers all day doing this. It's a never ending process and during spring and fall migration, the queue sometimes gets a little bogged down. Patience is a virtue.