Simplified approach in progress.
Tentatively working recursively. Will test to confirm.
Algorithm working, but too complex. Finding way to reduce cyclomatic complexity.
Beginning simplification breakaway.
Fixed missing paren error.
Reorganized and added alternate massive dictionary to try larger boards.
New 2D vector implemented.
Creation and blanking of isUsed 2D matching vector working.
Tentatively working recursion and at acceptable pmccabe level. Looks done.
Passed complexity test. Passed valgrind memory integrity test. Passed all posted dictionary-board tests on CS235 site.

Note that I added special snippets to stop it from printing space after the board letters or a trailing end-of-line. They are easily removable if they aren’t needed.