Well, ole Garibaldi is getting interesting. 😎 I checked the original 1879 Berzava page. This is an advertisement by the Liège gun factory Guil. Van der Straeten et Cie., and “Garibaldi-Damast” is indeed explicitly listed among the Damascus barrel grades/patterns. Even better, Rosen-Damast is listed separately. So Garibaldi-Damast was definitely a genuine Liège trade term by 1879 — while Giuseppe Garibaldi was still alive. That still doesn't prove that the pattern was named after him, but your joke may have been closer to the truth than we thought!

[Linked Image from brauchitsch.com]