Yes, all the TBFs are in Acknowledged mode.
Interestingly, the LLC Throughput indicators “GPRS_DL_LLC_throughput_per_GPRS/EGPRS_ack_TBF” give even stranger values. The values for the BSCs done exceed even 5Kbps :). Also, note that the denominator used in this formula is the same one that we are suspecting to be wrong (GPRS_DL_active_connection_EGPRS_ack_time*1000). So, we cannot expect even this indicator to give correct values. I wonder if someone has devised a new formula with new observation period which depicts the true throughput values?