For the moment, the best independent evaluator seems to be Stripe themselves. Hopefully they'll keep updating their apparently excellent evaluations:

https://stripe.com/blog/first-negative-emissions-purchases https://github.com/stripe/negative-emissions-source-material...

CarbonPlan is doing a great job bringing transparency here by analyzing and publishing proposals to the major carbon removal programs to date (Stripe and Microsoft): https://carbonplan.org/research/cdr-database