are there any lisp implementations or 3rd party libraries that support dotnet or com interop

Allegro Common Lisp and IronScheme has built-in support for COM. You can get any Common Lisp that runs on Windows to talk to COM components or make it act as a COM server by using CFFI.

I don't know if it's COM, but Edi's RDNZL is "more or less a foreign function interface for .NET languages like C#".

Racket and newLisp are also accessible from com.