Based on New Braunfels site Landa Park has no camping (nbtexas.org)
New Braunfels, TX - Official Website - Landa Park
but Landa
RV & campground does
Landa RV & Campground
2 COE parks in Canyon Lake, (Canyopn Park and Crane's Mill)both on FM 306, thank Shannon for the link
Wild Texas Parks: Canyon Lake Parks - Canyon Lake, TX
We stayed up river in the pop-up (when we had it) at another park that was private but I can not think of its name.