#3 One more chance
The most straightforward way.
For some reason, Vince McMahon finds it "best for business" to give Becky Lynch the last chance to qualify for the RAW Women's championship match.
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However, before Lynch can go on to face Rousey, she has to defeat someone. That "someone" could either be 'the Irresistible Force' Nia Jax (since Becky has some sort of unfinished business with Jax) or the Queen - Charlotte Flair at Fastlane or even WrestleMania.
If Lynch were to face Jax, the main event of WrestleMania 35 could become a triple threat match between the champion Ronda Rousey, Charlotte Flair, and Becky Lynch - which would still agitate a lot of fans. However, a better solution would be to have Charlotte Flair taking on Becky Lynch, with the winner getting a title shot against Ronda Rousey at WrestleMania 35.