Students using the same flawed online solution sheet as the grading TA
If the online sheet is incorrect and you suffered because of it, and if you have proof that the TA used that sheet, then you should point out to the professor of the course what has happened. 

But, ask for a a comparison between your answers and those that the TA suggests. This will make it clear. The other students may suffer or not, but that is up to others. You have a right to a correct evaluation of your work and the professor should be made aware of online solutions - especially if they are incorrect and misleading students. 

One set of students getting credit when they've broken rules and other students suffering when they have done the correct thing is the worst outcome possible. 

You don't need to accuse anyone. Point out the online sheet. Point out the (matching) solution rubric. Show your own work and ask for a fair evaluation.