It can be a difficult injury to diagnose.
When I did mine, it took 3 Dr's, 2 x rays and finally an MRI 2 months later to determine I had completely ruptured that and my meniscus and would need surgery. I couldn't walk, but the only physical evidence of an ACL tear is to test mobility in the joint, and mine was initially diagnosed (twice) as a sprain as my other ligaments and muscles in my leg seized to prevent the supposed movement they were looking for. Even Bolasie got up and tried to carry on with his.
Was unfortunate for Gosling, and I suppose the best thing is to err on the side of caution in these instances, but if Gosling felt OK, its a call anyone could have made. I knew something was up because I couldn't bend my leg or put any weight through it without extreme pain, and Dr's still told me otherwise.
Aside from that though, he still has a great reputation and was well liked, don't see the problem in this whatsoever.