Hey there @wlandesman --- SCP works over SSH, so you can just use the same port/user/password combo you use to log in. Here is an example of uploading a file (I just manually verified this using the 2018.11 AWS image):
$ scp file_to_upload.qza qiime2@54.245.166.26:~/
qiime2@54.245.166.26's password:
file_to_upload.qza 100% 0 0.0KB/s 00:00
This dropped file_to_upload.qza into my homedir on the server:
$ ls
file_to_upload.qza miniconda miniconda.sh
Give that a whirl and let me know how it goes. 
