[goodcanadian]

That is addressed in the article:

But a subsequent project, JCMT–Venus, designed to study the molecular composition of Venus’s atmosphere using the James Clerk Maxwell Telescope in Hawaii, offered a possible explanation for these disparate findings. Researchers tracked the phosphine signature over time and found it could only be detected at night, as it was destroyed by sunlight. They also discovered that the amount of gas in Venus’s atmosphere varied over time.

[MarkusQ]

At some point I expect they'll discover that it can't be detected in the presence of skeptics. At least, that's the usual trajectory. I'm all for any sort of planetary science missions, but this seems more faith than logic driven. For example:

“There are no known chemical processes for the production of either ammonia or phosphine, so the only way to know for sure what is responsible for them is to go there.”

This is untrue on multiple levels. There certainly are known chemical processes for producing both, ammonia is fairly common (e.g. huge clouds of it on the gas giants). Plus it still seems likely that what they detected was SO₂[1] which is also quite common and expected; if the problem with your discovery is in the interpretation of the measurement, confirming the measurement doesn't change that.

In any case, I'd lay long odds that "going there" doesn't resolve the issue any more than debating it here has.

[1] https://www.washington.edu/news/2021/01/27/phosphine-venus-s...