Sorry, Mr. Lewis Page, but these guys are almost certainly only a temporary problem. The important point is in this paragraph:

[…] And that’s not all. The reborn, undying gelatinous blob-cyst monsters can also “spawn” hundreds of genetically identical clones of themselves, each of which is also immortal and able to replicate itself at will using its own former guts, muscles or whatnot, transformed for the nonce into a thicket of supplementary genitalia. […]

“Genetically identical clones.” Biological history is full of species that develop asexual reproduction of one sort or another. It’s fairly easy to do. But though they might be successful for a time, they’re probably on “the fast track to oblivion:”

[…] But if they are, they may be short-lived. The evolution of traditional, female-only asexuality typically leads to a swift extinction. We know this because although such species frequently evolve, they don’t stay around for long. If you look at the tree of life, female-only asexual groups are all out on the twigs: there are no great asexual lineages equivalent to fish or birds. Instead, the asexual groups are a few species of snail here, a dandelion there. […]

The reason is fairly obvious, when you think about it. They’re all genetically identical. That means no individual differences in anything, including their immune systems. Their only source of genetic variation is random mutation, which is notoriously slow. A single successful virus could wipe them out, since they’d have no way to adapt to counter it and no portion of the population could be less vulnerable to it.

The bottom line: there’s little to worry about here, in the long run.