Title companies don't like Collector's Deeds in MO

[Sylvia B.]

We are considering buying a parcel next door to one of our rentals and have run into an issue. The title company that we use will not issue title insurance on any RE that has been through a tax sale in the last 10  years. Neither will the other title company in town.

Here is the timeline on this parcel. 
2013 - Collector's Deed issued to the city due to a lien placed on it for the expense of demolition of condemned house
2016 - Declared excess property by city
2017 - Sold at auction to an acquaintance of ours who intended to build on it
9/2018 - Owner changes his mind about building and agrees to sell it to us for $5,000

Now, $5,000 is no big risk to worry about someone clouding the title by claiming that proper procedures weren't followed and trying to redeem it, BUT we plan to put about $120,000 into building a duplex on it. 

It is my understanding that in MO an interested party (lienholder, owner, or heirs) has one year to redeem and once the Collector's Deed is issued, they're out of luck, but if so, why won't the title company issue a policy for 10 years? I don't know if they are overly cautious, or if there is something I'm missing. I have an email out to my lawyer about this, but thought I'd just throw it out here on BP to see if there's any discussion.