Weird Quartine Glitch..

so? last friday, i was playing quaruntine and one of the afk specialist zombies had a freakin SHOTGUN!!!
i got screenies, but i cant upload them

everyone who becomes a zombie and dont move , still have there weapon , when they mouse there mouse/ walk / slash / anything , they become normall zombies

and this is the same as in some rooms u find a flying scope or flying silencer , or a texture bug , when u see some walls textures flying in the air , stuck to another wall