It appears the city of Frederick, Maryland decided to renew the lease to its stadium with the Frederick Keys, the affiliate of the Orioles:
The article cites the city’s lack of transparency as a concern as the Atlantic League’s bid could have been a stronger bid in terms of revenues for the city.
Delving into some history of the independent baseball leagues, this is not the first time that the Atlantic League has had to forgo a city due to the Orioles. In the early 2000’s, the Atlantic League had a team in Bel Air, MD. The team left because of the Orioles bringing its single-A affiliate to the area:
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