Second generation imaging suite where the shielding is the only reason the rent works

Sitting with a 9,400 sf building, two suites, one of them a former imaging tenant that left behind lead-lined walls, a reinforced slab section and a 400 amp service. Seller is pricing that suite as if the shielding is worth $40 psf of avoided TI to the next imaging user, which is how he gets to $3.9m.

My problem is that the pool of tenants who value it is tiny. Within about six miles there are maybe four groups doing MRI or CT, and two of them are system-owned and put imaging on campus. Everyone else looking at the space is primary care or dental, and to them the lead lining is worth zero and the reinforced slab is a demolition line item.

So the suite is either worth a premium to one of two realistic tenants or it's worth less than plain shell because someone has to strip it out. I don't know how to underwrite a bimodal outcome like that. Do you run it as generic office rent with a downtime assumption long enough to find the imaging user, or price two scenarios and weight them? And has anyone found that the shielding actually survives a modern equipment spec, or does the next MRI user tear it all out anyway for a different bore size and cooling load?