Rittenhouse Used His Forward Assist

Last night I watched part of Rittenhouse's interview with Tucker Carlson wherein he described how he came to be guarding a couple of car lots and came under attack. Being the gun nerd, it caught my attention that Rittenhouse mentioned that when Gaige Grosskreutz raced up to him, he (Rittenhouse) noticed that his bolt was open slightly and he used his forward assist to close the bolt prior to shooting Grosskreutz. 

It is impossible to know for sure, but it may be that the all of the movement while shooting may have resulted in the bolt not fully cycling, or a cartridge catching (it is a push-feed system, after all). But I suppose this should put to rest the idea that the forward assist is completely useless.