You think that is going to work? Unlike the last time, this planned visit has picked up a lot of attention in the media. The BBC are reporting China's threat of military action. Even Republicans have taken up Pelosi's cause and are egging her on to go.You're on the right track but could go further. I offer the yanks a simple solution to back down without losing face:
Get Tsai to announce she caught covid and can't receive anyone
There problem solved.
It would seem awfully convinient for it to be cancelled for COVID again, it would be called out as a lie. What if it got out that Tsai was faking it? It would lead to trust issues as well as looking weak.
It would probably be better to just say you don't want WW3 and drop it, like the Ukrainian mig transfer.