Do we follow Mom's wish of "live by whatever means" or family decision "quality of life"?

My mother was my father's primary caregiver, he has parkinsons and alzheimers, she's much younger than him and suffered a traumatic brain injury after falling in the hospital, after a long and painful road, she was able to come home with extensive needs but had a setback (seizure) and has been in the hospital/another surgery/subacute since then, she was in a temporary long term placement and all pt/ot ended due to insurance, we were in the process of having her transferred to a different location where pt/ot would be included, but she had a setback is now back at the ICU.....everything is "maybe an infection", "maybe a slight pneumonia", maybe it's neuro-related, maybe this, maybe that.....i get it, it's the complications that happen not only after a TBI but also being in a hospital/long term setting/not moving around.....here's the main question: she's currently on a vent & pulmonologist is recommending trach instead since it's more comfortable, less chance fore infection, and it would be easier to wean her off (if that time comes).....my entire family is aware of my mother's wishes which is use whatever means possible (considered a "full code" at the hospital), there is a sibling or 2 that is talking about "quality of life", etc....but who are we to determine that?....not to mention these are the same siblings that have created such family drama since this disaster are completely disconnected ....the doctor made it seem that the trach would be common practice procedure. If the recommendation is to do the trach, can certain family members refuse this, others (me included) want to proceed and i think by not making a decision, they are basically making a decision which would probably end her life sooner....one sibling is already talking about having hospice involved, etc.....only God has the answer about when it's time to leave this hell, as far as durable power of attorney, me & my sister share the medical and i have legal, however, this is also a source of extreme tension since some of the siblings refuse to acknowledge this document.....we were actually in the process of proceeding with co-guardianship but one sibling is contesting everything, he has serious issues (a whole separate story).....i'm severely struggling because i know what my mother wants regardless if some of us think otherwise.....i don't know want yet another battle on my hands but then again it may be worth it in the end to honor my mother's wishes.....any input is greatly appreciated.....