Dillard's took over the old Scarborough's department store building in the late 80s I believe, becoming a separate Men's and Children's store. The original/main Dillard's store remains where it is today.
This is the building that originally housed the Scarborough's
The Montgomery Ward's store at Barton Creek closed in 2001 (as with the rest of the chain) and was replaced about 2 years later by the Nordstrom. They completely tore down the MW store and built the Nordstrom from the ground up.
The only Joske's we had in Austin was at Highland Mall. Dillard's took over that store in the late 80s as well.
As for Foley's, they were all converted to Macy's around 2006, which included the Highland and Lakeline Mall stores in addition to Barton Creek. Foley's was also set to open as one of the anchors at the Domain but instead opened as a Macy's (about a year following the conversion of the other stores).