I don't know the full story - and it would be indiscreet to say more.
But knowing that it takes time to trademark a name, I would think it likely that the TM owner "reserved" the com when applying for the TM, and our lad came along in the meantime and thought he would try to build on the co.uk because only the com was registered, and it wasn't being used, along with anything else.
Interestingly, the net, org, info and org.uk have all been taken by other people since the TM has been registered - I'll bet they got stroppy letters, too.
I keep finding situations like you mention, where a name is registered in a lot of extensions, but there is no-one doing anything with those domains, and the org.uk is available.
I'm sure it is possible, when there is apathy in the other domain owners, to build on the org.uk. I have seen it done, building on the .net and a hyphenated co.uk to get traffic through sites, when the "big" extensions are taken and parked.
When your domain is the only one providing info, the fact that it is org.uk is immaterial, as long as it gets indexed and people find the info.