Turned off Telnet and Password on the server.
He still got invalid password BUT! also extra issues.
2023-07-19T04:52:48 3063.318 WRN [EOS] [LogAnalytics - Warning] EventCache either took too long to flush (1.296 ms) or had a very large payload (0.609 KB, 1 events). Listing events in the payload for investigation:
2023-07-19T04:52:48 3063.318 WRN [EOS] [LogAnalytics - Warning] EOSSDK.HTTP.Complete,611
2023-07-19T04:52:57 3072.569 INF Loading and creating shader control textures took 11211ms
2023-07-19T04:53:05 3080.573 INF Loading and parsing of generator took 8003ms
2023-07-19T04:53:23 3097.748 WRN [Steam] Tick took exceptionally long: 45 ms
this caught my eye, this is new.
he can also Cannot rejoin the server after the crash.