That clip is compilation of many videos, not all of them are actual battle of Alam el Halfa. That is what Thondoror means. Correct me if i'm wrong, they also used some Rommel footage from Tobruk offensive as well.
Most people referred Alam Halfa battle to the early El Alamein southern sector offensive by the German Panzer & Italian Divisions. Not the general campaign of El Alamein or the famous second battle of El Alamein (which is won by the Allied, hence the turning point and repeated mentions), which according to Thondoror, is where the Sherman Tanks first appeared in the WW2 Western Dessert campaign.
IMO, you can't just believe all these seemingly credible documentaries thrown by specific subject TV channels. Even the critically acclaimed Apocalypse: World War 2 that has been aired repeatedly in NatGeo Channel also contained deliberate errors, some which are sadly learned from Hollywood sound effect: the typical Stuka's Jericho trumpet noise whenever a plane is downed in the footage. That distinct high pitch noise is only produced by trumpet-equipped Stuka whenever the dive brakes are engaged, not all falling/diving propeller planes sounded like that.
These documentaries are originally mute, the sounds you hear on TV are added much later, some are even re-colored to produce better images. That's why each of documentaries may have different sound effect for the same equipment (e.g. MG42 noise). It is better to refer the sound to FPSRussia's videos.