One school of interpretation, reflected in some accounts and alluded to in others, is that a lone figure on a small raft in the South Atlantic in 1942 presented an ambiguous signal to passing ships: it could be a legitimate survivor, but it could also be a decoy — a U-boat tactic in which apparent survivors were used to lure rescue ships to surface positions where they could be torpedoed. This interpretation would explain a freighter captain choosing not to stop without necessarily invoking racial motivation. Whether this or any racial interpretation is correct is not something the available evidence can establish with certainty. What is established is that the ship did not stop.
American aircraft — apparently patrol planes from the US Navy’s expanding anti-submarine patrol operations in the South Atlantic — spotted Poon Lim at least once. They dropped a buoy to mark his position, apparently intending to return or direct a rescue vessel. A storm moved the raft and made that position irrelevant. The rescue did not follow.
A German submarine surfaced in his vicinity. The interaction between U-172 and Poon Lim at the time of the sinking is documented; whether any subsequent submarine encounter occurred is drawn from his own testimony and attributed to him in several sources. U-172 would eventually be sunk on December 13, 1943 — more than a year after the Benlomond’s sinking — in an engagement west of the Canary Islands, with aircraft from the escort carrier USS Bogue and four American destroyers contributing to its destruction after a twenty-seven-hour engagement involving hundreds of depth charges. Carl Emmermann survived the war.