The evidence is there, but some people refuse to accept. The claim is not implausible, unfortunately - it happened in other countries (e.g. Chile). Either way, their history of war crimes and atrocities goes all the way back to the start of the invasion, and continues to this day for everyone to see:
The first link is about a dog attack, but absolutely nothing about dogs being "trained to rape". The second link is nothing specific, just an entire subreddit devoted to anti-Israel propaganda.
The first article just shows a sliver of the crimes they commit, documented by a western source. I found an article that talks about how similar crimes with dogs raping prisoners was done in Chile, so it's not far fetched at all that the israelis are doing the same.
You said "the evidence is there" about Israeli rape dogs, not some other allegation. An incident that has nothing to with rape isn't evidence, nor is an incident that happened in an entirely different country.
So where is this evidence that you say exists?