Maryland Non resident e file question

[Prometheus]

My client is a full time PA resident but employer withheld Md state income tax.  The non-resident return requests full refund of all Md tax withheld.   I intend to file Md non-resident e-file---but have a question:

1.  must one send a copy of PA return and copy of W2 to Md?

2.  If so, how to accomplish?  I've been looking for a way to upload information but can't find.  Does not seem to be a Md Form 8453 to forward supplemental iformation.

3.  Any suggestions?

Thanks