None have any offspring in the Horsetelex database.
Journey at Sea, Wise River, and Ruler’s Court don’t have any offspring in the Hippomundo database. Under Tack has one daughter listed, a mare named Pride of Kildare. She has one listed offspring, Hadley FDF (a 2007 gelding by Gastby) who has a USEF record through First Level dressage (last shown in 2016). Wise River doesn’t have any offspring listed.
Journey at Sea has one USEF registered offspring, a gelding named Chief Hightower, who doesn’t have any show record listed there. Same with Under Tack (one gelding, no show record). Wise River has no offspring listed in the USEF database. Ruler’s Court has one, a paint cross gelding born in 2015 who has no show record.
I’m afraid that is about all I could find.