No, they aren't: the second is irrelevant and unphysical. Highly-pressurised cores? Really? "Dense", I could buy, but:

• If there's blood supply, then (A) it can't be a much higher pressure than the blood pressure (unless there's some Rube Goldberg machine involving active transport), and (B) the tumour is reachable by treatments like this;

• And if there isn't blood supply, then the tumour's core is necrotic, and a treatment to kill the dead cells wouldn't do anything anyway. (Sure, killing the tissue that isolates a lump of necrotic flesh from the rest of the body might cause new and exciting problems, but somehow I think those might be preferable to incurable breast cancer.)

The second is just not a relevant criticism. The third, if it's an actual issue, can probably be worked around by tweaking the molecule slightly – and if not, suppressing the immune system isn't that difficult (it's a known side-effect of many chemotherapies). The first, if it's an issue, can be avoided by injecting the medicine near the target site.

I agree that this treatment might not work in humans, but all the AI's done is taken a generic list of potential concerns, and inserted technobabble to try to make it match the scenario. If you want generic criticism, see https://news.ycombinator.com/item?id=47209076: at least that's true.