Runtime Error - something to do with Autorest

Start by reproducing oad compare derefd.json derefd2.json with the reported Node and oad versions, then inspect the AutoRest entry point at node_modules/autorest/dist/app.js and its @autorest/core version selection. Done means the command can locate the required core package and complete the comparison without the reported runtime error.

I installed it like so:
npm install -g @azure/oad

My env:
OS: MacOS Monterey 12.4

oad ver: 0.9.7

$ npm --version
6.14.16

$ node --version
v12.22.12

$ nvm --version
0.39.1

Then, tried to run the command:
oad compare derefd.json derefd2.json

Got:
Error: Command failed: node /Users/ananrao/.nvm/versions/node/v12.22.12/lib/node_modules/@azure/oad/node_modules/autorest/dist/app.js --v2 --input-file=derefd.json --output-artifact=swagger-document.json --output-artifact=swagger-document.map --output-file=old --output-folder=/var/folders/_v/yt6hqgc91zs8r1zzwr8g5tb80000gq/T
Error: Unable to find a valid AutoRest core package '@autorest/core' @ '~2.0.4413'.
Error: Unable to find a valid AutoRest core package '@autorest/core' @ '~2.0.4413'.
at selectVersion (/Users/ananrao/.nvm/versions/node/v12.22.12/lib/node_modules/@azure/oad/node_modules/autorest/dist/src_autorest-as-a-service_ts.js:393:23)

at ChildProcess.exithandler (child_process.js:308:12)
at ChildProcess.emit (events.js:314:20)
at maybeClose (internal/child_process.js:1022:16)
at Process.ChildProcess._handle.onexit (internal/child_process.js:287:5) {

killed: false,
code: 1,
signal: null,
cmd: 'node /Users/ananrao/.nvm/versions/node/v12.22.12/lib/node_modules/@azure/oad/node_modules/autorest/dist/app.js --v2 --input-file=derefd.json --output-artifact=swagger-document.json --output-artifact=swagger-document.map --output-file=old --output-folder=/var/folders/_v/yt6hqgc91zs8r1zzwr8g5tb80000gq/T',
stdout: 'AutoRest code generation utility [cli version: 3.6.2; node: v12.22.12]\n' +
'(C) 2018 Microsoft Corporation.\n' +
'https://aka.ms/autorest\n' +
'info | AutoRest core version selected from configuration: ~2.0.4413.\n' +
'Failure:\n',
stderr: "Error: Unable to find a valid AutoRest core package '@autorest/core' @ '~2.0.4413'.\n" +
"Error: Unable to find a valid AutoRest core package '@autorest/core' @ '~2.0.4413'.\n" +
' at selectVersion (/Users/ananrao/.nvm/versions/node/v12.22.12/lib/node_modules/@azure/oad/node_modules/autorest/dist/src_autorest-as-a-service_ts.js:393:23)\n'
}