Assign multiple email templates to a single situation

Summary

Need more than one template option for emailing candidate an offer (new employment and promotion)

Content

We have decided to generate offer letters for internal promotions in TBE Recruit and would like employees to e-sign the offer.  We have the ability to email an offer to a candidate but the template for "Email candidate offer" has wording for a new offer of employment, not promotion.  I created an email template for a promotion offer, but Assign System templates only allows one template per situation.  Is it possible to pick multiple template or another way to accomplish sending out an offer for promotion with the e-sign link.  Thanks!