As they acknowledge Jeanne suggestion, the Earthlings and the Zarians assembled a team of experts in cosmic energy, linguistics, and diplomacy to establish a channel of communication with the Flame Seraph.
They utilized their advanced Rudanium powered technology to search a way of communication to make a device that could transmit messages encoded within cosmic energy fluctuations.
After a few years, the Earthlings decided to work without the Zarian civilization on this project, after all, without being a level 4 civilization, they couldn't even understand how to research it properly on the cosmic energy.
After a few times that Jeanne used her time related ability in her dreams since she could use it once a year, she finally was able to find a prototype device that could maybe lead them to interact with them.