z3 ERROR: unknown parameter 'model_compress'
Apparently z3 dropped this parameter and replaced it with "model.compact" without bothering with backward compatibility: https://github.com/Z3Prover/z3/issues/2704#issuecomment-554489258
Use z3 4.8.9, turn on debugging.
<6.827036,call_prover>Call_provers: actual command is: z3 -smt2 -t:10000 sat.random_seed=42 model_compress=false nlsat.randomize=false smt.random_seed=42 -st /tmp/why_b9efc2_zilch-T-wp_goal.smt2
ERROR: unknown parameter 'model_compress'