I called a mold remediation company to come do an estimate, 11k.

@MacKenzie ClintonThere is an enormous amount of panic and fear about mold and mold remediation in real estate these days.Here's a Wikipedia article to ease your worries about evil black toxic mold: https://en.wikipedia.org/wiki/StachybotrysIt's perfectly possible there's mold behind the bed for some crazy reason that's the tenant's fault, although highly unlikely in just 5 months of occupation.

If there was no disclosure about the (poorly maintained and over full) septic, there may be able to go to the previous homeowners for some remediation??

The dust test will tell you if lead is present, but the XRF test will tell you exactly where lead is throughout the interior and exterior of the home.Lead paint was banned in Baltimore in 1950, so homes newer then that will cost significantly less to remediate than those build before.

But I would still be seeking some form of legal remedy on the back end.

If there is a problem in the first inspection that they need to remediate, I understand going back over there, but other than that, it is intrusive and unneeded, in my opinion.If there is a repair request, you can go in at that time.At my company, we go in prior to lease renewals to make sure everything is good. 

Tenant will be charged for all damages to the Property caused by smoke, including cleaning fees, carpet cleaning, and re-painting if reasonably necessary to remediate smoke odor."

The tenant corrects their violation and all is good 99% of the time.Fear of evictions is ridicules and usually a excuse to avoid managing a property.If your overarching concern is that a term in the lease has been violated it doesn't make sense to then suggest that  the consequences of the only contractual remedy available to you for that violation should be ignored.

Not particularly, being able to name a parent company has been a long time common law remedy in the United States. 

We were really concerned at first but as we saw the test come in with just a few things such as the garages, or front door casing, some window casings, and the remediation was small, we realized it was all about prevention and up keep.