Loader.js MissingModule at runtime after upgrading ember-auto-import to v2

My app is on v3.28 of Ember. After upgrading ember-auto-import from 1.12.0 to 2.6.0 (and adding webpack 5), I'm getting a missingModule error from loader.js for dependencies of my app's addons. I'm sure the issue is probably something that needs to be reconfiged in ember-cli-build, but i can't figure it out. Can somebody help point me in the right direction?

Instance of this error: Uncaught Error: Could not find module lodash.merge imported from ember-rollbar-client/services/rollbar

ember-rollbar-client: 0.9.0 -> lodash.merge: 4.6.1

Package versions: ember-cli: 3.28.6 node: 14.17.0 os: darwin arm64 ember-auto-import: 2.6.0 webpack: 5.75.0