Chats about Moderation actions taken should be posted to the appropriate Server's Website rather than the RenX Forums, since this forum is regarding the game, rather than individual servers.
However
Tanks Exploding - Vehicle Death is recorded in the log, but it doesn't output to in-game since this could be a rather large amount of spam to the kill feed, and it can already be quite busy.
Players Dying mid sprint - This could be due to being killed by a sniper, especially 500 snipers, who have no visible bullet, and you can easily miss the kill message especially if a lot of people die in the same time frame. However if you don't see a killer attached to the kill feed, they could also have taken damage from the environment, although Died, does occur if a Mod/Admin kills a person, the player does not get listed in the kill feed as the Mod does not "Kill" the player, the server does.
Kicked for Mining - Mine Banning is a valid method of handling these situations, since if the player was new they are unlikely to be kicked for just Mining issues. Although this would be better off being discussed with the Server Administrator to ensure the mods are following the rules rather than discussed here.
Also all use of the commands are logged I believe by default, although that can be changed by the server owner. And many moderation bots that link to IRC would also record Mod/admin commands used.
So Mods and Admins can be held to account if necessary, but these situations should be dealt with on the server's website.