Travgen Timeline

I don't understand. Recently I saw a picture where the Dark Jedi Travgen is mentioned. And immediately there was a textual misunderstanding (highlighted in red). The problem is in the timeline. It is stated that Travgen is not as strong as the Emperor, rather twisted. Then it is said that after twenty years of meditation and so on, he became as strong as DE Luke.

Based on starwarstimeline.net, Adventure Journal #14 takes place in 13 ABY (with the exception of <>). Does this mean that the text about Travgen also refers to this year? Or is there no time frame at all in this text?

And here's another. The fact that he is weaker than Sidious does this refer to the time before meditation or does this also not apply to certain time frames?

It.