The WPFTS Pro version you are using is very outdated. Please consider upgrading to 2.46.x which is the latest. It has a completely new indexing and searching algorithm and it should solve your issue.
Yes, the algorithm thinks the number of words here is more important than the exact phrase... Ideally, if we could justify the relative weight for the phrase matches. Currently, it's too low for your case, but I think if we can double it, this could solve the issue.
I think to put this parameter to settings in the near future. Thanks!