Not enough evidence can be a reason. But I think that another reason is to find DT members that are available and have the willingness to properly check your findings, especially if they are not overwhelming (I say it hypothetically, with not relation to your posts, I didn't check them that good).

And asking DT for help would (as long as you don't spam) :
* get more attention
* help you make better reports if necessary
* get the users tagged

I can tell that I've made reports too (in my case for plagiarism) and nobody handled them. Sometimes it just happens... You may have to insist more and do as you think it's better.