[lance (2)]

The 'spinning' shows him tilting his camera sideways, which is impossible under normal movement. So he's most definitely using a script there. I doubt it's just a 'bug' with the camera because I have never seen cameras tilt like this before when spectating players in 1st person.
I've seen players call him out for using spinbot before on the server. About 3 or 4 of them claimed he was spinning unnaturally in deathmatch. Some claimed they just felt he was hacking.
I don't think the no recoil thing is from the spectating tool because I've seen recoil on it before (i.e the view flicking up, not just the gun animations). It's hard to believe the spectating tool just 'glitched out' because he is indeed using a spinbot, and hackers commonly toss together multiple hacks.
There are some external hacks which are really hard to detect for some games. I'm not sure if Gmod has some, but if it does, CAC would not be able to detect it as CAC searches for changes such as manipulation of sv_cheats and clientside lua execution (which requires sv_cheats to be set to 1, so thats a no-brainer). There are many ways to hack other than using Lua and changing sv_cheats on Gmod.
Source: ( Í¡° ͜ʖ Í¡°)