IIRC, the Amazon kernel build did not (at the time of this project start) ship a complete set of USB serial modules (dynamically loaded drivers, loaded by the kernel).
See first post, where this work is based on the adding of mouse support (which also requires USB serial modules).
Start at post #1 here (or better yet, at the mouse support thread, which this extends).
Look for a mention of the kernel build information, it MUST match what you just listed or the modules have to be rebuilt.
(The kernel will not load modules not built specifically for it.)
OR
do a modinfo command on the modules that this (or the mouse support thread, if KL is using those modules) - they must match:
Code:
3.0.35-lab126 #2 PREEMPT Tue Dec 4 17:14:27 PST 2018 armv7l GNU/Linux

This thread was started Sept. 2016, so the modules could not have been built to match a Dec. 2018 kernel.

As I originally posted, build the required modules to match your kernel build or get someone to do it for this project thread.