If you want something like RCML, why not use RCML?
Ethernet KRL module or JOpenShowVar would enable to send tasks.
RCML: I have read this possibility, but didn't find how it realised on KUKA. If you know it please share.
JopenShowVar have seen as well, but the discribed way was not helpfull (https://github.com/aauc-mechlab/JOpenShowVar). Maybe there are some other.