I'm just wondering if anyone has any practical advice directly on the subject at hand, about how to make it work, instead of how things don't work.
Your statements are based on the assumption that the device you have can be modified in the way you want, and all you need is instruction. You seem to be ignoring the WAY more likely case that the device cannot be modified in the way you want.
You mention a resistor in series with the antenna in three posts. Yet, there is nothing, in the very scant information you have provided, to indicate that such a resistor actually exists in *your* device. The video is for a completely different product, almost certainly is bogus, and contributes nothing to what we need to know to give a definitive answer. (In fact, the video is a huge self-contradiction; the words he says about the mod he is making and the images of the mod are absolutely *not* the same.) There is nothing in any of the images you have posted that looks like an antenna, but we have not seen the entire product, any connecting cables, etc. It is possible that the audio input wires are being used as the antenna, but that cannot be determined from what you have provided.
Another inference is that you (and/or others) think that if a resistor is in series between a source and something else, it must be limiting the energy into that something else. While this often is the case in a DC circuit, there is a huge difference between DC circuits and field theory. RF amplifiers and antennae are designed using the Maximum Power Transfer Theorem (MPTT). It is entirely possible for a series resistor to increase the total power delivered to the antenna.
Advice #1: Don't get sucked into a spat with AG. You will lose. He has way more stamina than you think. He knows a butt-load about audio, but it often comes with a dose of half-baked ranting. Just walk away.
Advice #2: Lose the attitude. Asking for advice, and demanding the answer you want, are not the same thing. And, you went from one to the other pretty fast. You came to this forum to get advice from people who know more than you, and that is exactly what you got. Don't blame the forum for you sense of dissatisfaction.
You came here with misinformed expectations. Your base assumptions (first, that the resistor exists; second, that changing/bypassing it will increase radiated power) are at best unsupported, and almost certainly wrong.
And - this forum is way more friendly than some others. Not the best, but enough above average to matter. On <xx> you would have been shredded by now, and the thread closed and locked. Note that I am in no way condoning that behavior, and in fact push back against it when I can. But I also push back against bad manners.