Gold Card holder working from Taiwan for foreign (US-based) employer with no Taiwanese presence

Work for them as an independent contractor / freelancer. You might even consider starting a business somewhere in the world and pay yourself a salary. Then, your „employer“ will become your client and should not need to deal with any of those aspects.

Of course, then those questions will shift from your client to you - also see my thread for some time ago Working remotely for a self-owned foreign company without an office in Taiwan - legal?