The reason is CS:GO is not community server friendly.
Valve made it to rack in cash from box openings and they added some mods like competitive to attract the players so they can show off their items.
So when you find out about a wierd bug, in a lot of cases you will have to figure this stuff on your own. I get wierd ass bugs all the time which i NEVER had on CSS,Gmod,CS 1.6. But these games on the other hand are actually real polished games that had community in mind.
Now that I am done with my little rant, this is what you are talking about
:
https://developer.valvesoftware.com/...o_player_start
So it has something to do with spawn points in the map, so this means your deathmatch spawn points are still working on awp_lego_2 aswell. I don't know which DM plugin you are using. It can be a lot of stuff.
I doubt this is reason for crash though.
The first error.mdl probably is.
If you have this plugin or anything similar
https://forums.alliedmods.net/showthread.php?t=152898 disable it. If not disable every plugin to make sure its actually plugin issue causing this.
You can also install
https://forums.alliedmods.net/showthread.php?t=195008 so server ignores these warnings that are not actually causing crashes.