Professional Dota 2 player Roman "RAMZES" Kushnarev revealed the largest salary he received throughout his career. Answering the question during a stream on Twitch, he said "twenty." Most likely, he meant $20k per month.
[What was your maximum salary?] I cannot tell you the exact figure. I had a large salary. <...> Well, more than twenty.
RAMZES played for multiple teams in his career, but realistically, only a few organizations could've afforded to pay such money. The former CEO of Virtus.pro, dvoryrom, earlier claimed that their salaries during peak times were between $10k and $20k. From 2019-2020, the player was a part of Evil Geniuses. At the time, RAMZES was in decline in terms of results but still considered to be a top performer.
The remaining candidate is NAVI, but the player was part of it for only three months in 2021, and was soon released. While the organization was financially pretty strong, their Dota 2 team was in decline for a while. It would be hard to justify such a salary compared to the other members, and for a player who had no recent achievements.