What did happen:

Resident Evil 4 was initially released exclusively on GameCube in early 2005 (North America: January, Europe: March)
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Capcom had planned the game as part of their “Capcom Five” titles to support GameCube, but due to poor GameCube hardware sales and smaller install base, they quickly scrapped exclusivity and ported RE4 to PlayStation 2 in late 2005 .

The GameCube version sold around 1.6 million copies worldwide, while the PS2 version sold over 2 million (some sources cite 2.2–2.3M)
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What didn’t happen:
1. RE4 did not “sell horribly” on GameCube

GameCube version’s ~1.6M copies was strong for a third‑party mature‑rated game on GameCube. It sold well in its niche—not a total flop as implied ≠ "dog milk" sales
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2. Capcom never neared bankruptcy over RE4

There’s no record of Capcom facing bankruptcy risk due to RE4 or needing to port it to avoid going under. Capcom remained financially stable throughout 2005–2007.

3. The PS2 version didn’t “save the company”

Though porting to PS2 significantly boosted sales, RE4 was already widely praised and selling respectably on GC. PS2 boosted overall reach by several hundred thousand copies, but not to the extent of being existential lifeline for Capcom
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