After mucking around with Jasspa, I still really wanted to get emacs running. I went back to looking at kbox2. I wanted to try running the native emacs port under kbox2 with the hope that I'd get a fully functional dired and tramp.
I was able to install kbox2 in the root of the emacs directory, which then let kbox2 and emacs see each other. I fired off the kbox_shell and tried to run emacs.bin. It almost worked. It fired up and then eventually segfaulted after running through a bunch of initialization.
I ran emacs -q -f -batch and a few other parameters and got a useful debug message. It said "apparent cycle of symbolic links /sdcard". It turns out that kbox2 has some magic to symlink /sdcard to sdcard. The solution was to eliminate any symlink hops and directly symlink /sdcard.
Here's the initialization script that got it all working:
rm /sdcard ln -s /android_root/storage/emulated/legacy /sdcard rm /storage /data/data/com.zielm.emacs/emacs.bin
It ran perfectly. I then just installed the dropbear package and was delighted to see tramp open up a file on my remote host through ssh.