Linking user with our org's server. Use oauth or invite?

We have a server that manages all the members of an organisation (a volunteer run convention) and also have a Discord guild. Currently membership to the guild is managed separately to the org's account server. We would like to make it so that roles and membership to the Discord is controlled by the org's server.

Currently we have done this using oauth, where the user links their Discord account with the org's server. Basically the bot associated with the server makes the connection, based on the user's authorisation.

We are wondering whether it would be better to do this via a one time invite link instead? I'd be curious to hear how other people have addressed this.

Our server is written in NodeJS.