You didn't say what kind of facility you are in. LTC? Step-down?
A concern I have is that we don't really know what the other nurses did or didn't do for sure. They may have slipped in the room while you were somewhere else, did an assessment, and believed the guy to be OK. (Although I don't know how they'd come to that conclusion if he had pulmonary edema and an abnormal heart rhythm!!!)
Another concern I'd have is the patient outcome. Would his condition have been significantly changed by earlier intervention? Was emergency transfer avoidable? (probably not, by the way). However, if the patient should expire, and the wife remembers that she was trying hard to get someone's attention . . . it is possible that this could end up in court. So, like sjoe said, document for your own records.
I also suspect that you are unsure of yourself so you didn't press the issue when "the nurse" said he didn't need to be suctioned when you felt that he did. In the future, you need to get more insistent. Say something like, "Please come assess Mr. So-S0 now. I believe he is in distress." You say it that way because you did not do an assessment, so you really didn't KNOW he needed to be suctioned. You arrived at a conclusion before you had all the facts. That's OK, I'm just wanting you to develop critical thinking skills, too!
You report what you actually see and hear, not your conclusion. So, report to the charge nurse that Pt. is cold, nonresponsive, audible wet labored respirations, family member at bedside is upset, etc. Report what you see and hear, not your conclusion.
After you report that, your responsibility ends. If the nurse won't go assess the pt., you can ask him/her why or what her rationale is for not seeing the pt. That will also give you an opportunity to report to her in more detail why you believe the pt. is in distress and needs immediate attention.
I think part of the problem here was a communication problem. Some of the suggestions above might help eliminate those. However, if there were true negligence, then, yes, it needs to be reported as high up the chain of command as you need to go to have the problem dealt with. But, again, once you report it, your responsibility ends.
I'm so glad to see someone who is caring and concerned about your patients! You're going to be a great nurse! Love your avatar, too!