Alright, after much more experimentation, it turns out that what I'm trying to do *can* work, provided that the formatting of the log backup file names exactly matches what log shipping is expecting.
I'll be working on a blog post detailing everything discussed here as well as how I solved each step. Will include a link when it's up. Thank you everyone for your help!
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Bob Pusateri
Microsoft Certified Master: SQL Server 2008
Blog: The Outer Join[/url]
Twitter: @SQLBob