Using many, numerous SQL checks and validation tools, there are no issues in the data having LAT outside of -90/90 degrees>
SELECT a.OBJECTID, b.n,
a.SHAPE.STPointN(b.n).Lat AS Lattitude,
a.SHAPE.STPointN(b.n).Long AS Longitude
FROM dbo.STATES AS a, num_seq AS b
WHERE b.n <= a.SHAPE.STNumPoints()
ORDER BY a.SHAPE.STPointN(b.n).Lat, b.n;
Shows all LAT falling well inside -90/90 .
In addition, SSMS and Arc Catalog seem to handle this data nicely. I can use the data in numerous SQL expressions and no errors occur. Only when displayed in Arc Map does the error occur, which leads me to suspect that this is an issue with the Arc Map translation of the SQL Geography Type?