Monitor GitHub pull request without commenting

I'd be happy to be proven wrong and delete my answer... but I think at the moment the answer is no. Not even the API for github Issues seems to allow this.

For your example, I think your best bet is to search for all labels except [bug]; or create a new label "non-bug". :)

You can of course contact github and put this "filter-out" feature in their suggestion box.

Github allows for repository transfer, requesting this transfers its issues, wiki, stars, and watchers. Bear in mind that when you're doing transfer across user accounts, Github doesn't allow for a fork to exist in the target network.

Transferring a repository gives the new user immediate administrative access to the repository—including its code, issues, pull requests, and releases

Before you transfer a repository, keep these things in mind:

The target account must not have a repository with the same name, or a fork in the same network.

To initiate a transfer, the owner of the repo should do this from Settings → Transfer.