Rewrite causing problems with domain

I've searched the community and KB, but didn't see anything quite like this. Essentially, if I add a subdomain to rewrites (ie, bob.example.com), it works as expected, giving the IP I provide for that subdomain. However, if I do a base domain (ie, example.com), I get a few really random issues:

1) Some domains that aren't the original TLDs, such as .app (ie, bsky.app), will get replied as part of the base domain. Ie, I put in example.com=192.168.0.1, then if I go to bsky.app, it resolves it as bsky.app.example.com=192.168.0.1.

2) This only happens with non-original TLDs, but seems to happen to all of them. Thus, any .app or similar domain becomes .app.example.com. 

3) It doesn't happen at all with "normal" TLDs. Ie, anything with .com/.gov/etc will always resolve as-is.

4) If I add a subdomain, such as bob.example.com, this issue doesn't happen. It's ONLY if I add a base domain, and it happens with any base domain.

Where this is causing me grief, is I have a local domain. Normal protocol here is to add the local domain as a rewrite to the domain controller. However, if I do that, ALL .app or similar TLDs are broken. 

How can I get my rewrite pointed to the domain controller, without breaking dozens of websites for all users? Surely someone's dealt with this.

Examples:

- Add rewrite for example.com = All later TLDs break, and are rewritten and resolved as (whatever).example.com, even though example.com wasn't part of the request.

- Add a rewrite for bob.example.com = Everything works normally, and bob.example.com rewrites as intended.