I searched for info on whether the IRS requires an original signature by ERO...couldn't find any answer here so I searched the IRS. Here is what they say:
Requirements for use of Alternative Methods of Signing—Effective October 15, 2007, the IRS allows EROs to sign Form 8878, IRS e-file Signature Authorization for Form 4868 or Form 2350, and Form 8879 by rubber stamp, mechanical device (such as signature pen), or computer software. The alternative methods of signing must include either a facsimile of the individual ERO’s signature or of the ERO’s printed name. EROs using one of these alternative means are personally responsible for affixing their signatures to returns or requests for extension
Requirements for use of Alternative Methods of Signing—Effective October 15, 2007, the IRS allows EROs to sign Form 8878, IRS e-file Signature Authorization for Form 4868 or Form 2350, and Form 8879 by rubber stamp, mechanical device (such as signature pen), or computer software. The alternative methods of signing must include either a facsimile of the individual ERO’s signature or of the ERO’s printed name. EROs using one of these alternative means are personally responsible for affixing their signatures to returns or requests for extension