Was there another band of similar vintage who might have been in a position to capitalise on their nonexistence? I mean there must have been other rock’n’roll bands around, they can’t all have formed five minutes after Please Please Me came out. Sure every other label went out hunting for the next/their own Beatles, but there must have been extant bands they seized on (and promptly retooled using the Beatles model).
So, any band that existed pre-1963. Manfred Mann? The Dave Clark Five? The Rolling Stones - I’d guess they’d be the most likely as, unlike many of the imitators, they outlasted not just that initial flurry of Beatlemania but even the Beatles themselves. Or perhaps somebody even more bluesy? John Mayall with what eventually became the Bluesbreakers?