Currently tokens with random images that use the wildcard option don’t work because the URL is invalid. The wildcard support in FVTT is a bit more complex than the current system is using so additional work is required for it. An issue was filed in FVTT and fixed and expected for 0.5.2 which would make this easier.
I can either do the extra work now which will all be throw away later when 0.5.2 is out, or wait for 0.5.2.
Will depend on my other priorities