The outnumbered & thinly stretched RSA may have failed miserably in their attempt to annhilate the 28th. But one can safely doubt that the RSA failed as much as you suggest. The RSA may have been poorly deployed in the aftermath of the destruction of Nasir Oric's HQ, but they didn't 100% fail. The OpOrder was not to annihilate the 28th, only to retake Srebrenica and render the unit ineffective/inoperable for a while. Mladic wanted to get the war done with before next winter, he did not want to keep fighting this war. He was getting tired of the civil war, so he ordered the "the militarized safe havens" to be demilitarized in accordance to UN Safe Haven order.
The UN forensic experts testified that they found at least 600 KIA of the 28th. It is unlikely that intercine fighting among the 28th killed more than that.true, it would be very difficult to differintiate between a "Muslim" AK round or a "Serb" AK round. You can only speculate and never know if you are correct upon those testimonies. Of course, we know the crediblity of the UN/NATO experts have been, with the 8,000- 6,000- 1000 bodies....
No matter how well planned, Gen M. never suspected that a few companies of RSA infantry could have rendered a full entrenched division into a mob of fleeing fighters. Gen. M. only wished to demilitarize the zone by making it impossible for the execution squads of the 28th BiH to operate.