it parses the V in XXXV as an element group

But that's not a problem because that leaves you with only V and R which add to 98, so you only need to add some others to get it up to 200.

A follow-up study refuted that. https://phys.org/news/2022-12-phosphine-venus-isnt.html

edit: A follow up to this follow up found that it had calibration errors and reported 3ppb on Venus. The original study however had 20ppb. https://arxiv.org/abs/2211.09852