In addition to the speculatory nature of the edit (we prefer to avoid speculation), the similarities between Timber and Halo's Gravity Hammer + rocket launcher are superficial at best; as you can see here.
Apologies for late response, I didn't expect someone to actually want to discuss something instead of just yell at me for being wrong.
I disagree strongly at it merely being superficial, you don't see hammers that look like that often at all, nor side by side double barreled rocket launchers and creative liberty while keeping the overall theme of the original is hardly a new concept.
If you showed either of these to Halo fans I'd wager 90% of them would spot the similarities. Besides, let's not forget without Halo being the basis for RvB Rooster Teeth and by extension RWBY would never be a thing, so a few nods to Halo snuck in here and there should not be in anyway shape or form surprising.
I think a few people discussed this on discord after you brought it up. You have valid points, but it's still not really enough to outright say it's inspired by the gravity hammer. It's similar, but not enough. It could very much still be a coincidence.
At times like these I really wish the writers/concept artists/modelers would throw us a bone once in a while and actually respond to simple questions like these -.-