If it’s a “trusted” source, as in a popular one, such as a certain link from a certain girl that is fit, yes.
Otherwise another option I’ve done for a while was buying cheap keys from greymarket type resellers, though for those I only did them from AAA publishers never putting their games on sale and on a second account (idea being you minimize risk and if something did turn out to be a stolen key, which was a problem for a while on those kinds of sites, a chargeback isn’t going to hurt a AAA publisher as much as an honest small published in house indie dev team).
GreenManGaming is a legitimate reseller, in a similar fashion to humble bundle or similar sellers.
I also do not like them because their keys if you are buying on sale for a new launch, their keys are usually UK based as they are UK based and they will not let you play on sooner launch dates, as I learned with Mirrors Edge Catalyst’s release when I wanted to play on day 1 and should have bought direct through origin, but instead now I had to wait a week, and they did not offer a refund policy.
So instead I bought the game again on origin and gave away the other key as a free giveaway to spite them 😂