He is halfway there. But deafened and others who don't sign with hearing loss, attain many skills deaf do not actually utilise effectively themselves because of sign reliance, because they rely on the translator. Not enough individual effort is made by deaf signers to research what they need to know.
Most Deafened and others NEVER attend meetings without proper backup and research into the meeting point, they know they have to rely on assistive devices, a 'good' day, and maybe poor lip-reading skills and all that entails. So plan ahead ALWAYS or don't risk going there being left out. Non-signing 'deaf' sectors acquire skills to 'direct' conversations with hearing people to 'steer' them towards a response or answer you require, it is, however, a SKILL, and you have to avoid dominating spoken outcomes of people to the exclusion of 'listening' to what is going on and thus being assumed rude yourself.
Not many non-signers are adept at it, but some are. You can be thrown by issues being raised or discussed you don't know anything about, again, the response is pretty simplistic, you stop there and ask them to explain what that is, always ensuring to avoid the 'nod' when you really are NOT following what is going on, or you are the architect of your own ignorance. Without research first and a lot of awareness by yourself, you will struggle. An interpreter has to be organised too, don't sit there passive expecting THEM to read minds or understand issues either, you have to organise your support at what best works for you.
I've lost count of sign interpreters booked who immediately commence translating what is being said, and the deaf just going with it hardly ever asking questions about what they need an explanation to understand. Plan, Plan and Plan again, get the rundown prior to any meetings re topics to be discussed, if you see some you have no idea about, then, ask for details before you go. E.G. If you want a trip to the seaside by rail, you ensure you know the train times and costs etc don't you? Then you are in with a shout at least as to asking for wider explanations on subtopics etc. Hearing meetings are geared around hearing people. Once you understand that and make that point things get easier. Sit near the action, don't sit at the back that suggests you are avoiding things. If you can't effectively see who is orating you are out of it.
Business leaders in the UK actually looked to deaf meetings to understand how to effectively communicate in a hearing one. Deaf etiquette generally (Not always!), frowns on too many signers 'speaking' at the same time, its rude! However hearing people don't go the same way, you will see private whispered conversations and random points put or clarified during a topic explanation and quickly lose track who is saying what.
Hearing terps go along with it to a large degree its a 'norm' for them too, or they may adjudge the 'aside' is not relevant to the main issue or would require further in-depth explanation the terp feels there is no time for, as stated, train your terp. Most terps don't specialise in particular topics or areas to that effect they may follow less than you, their job is to translate what is said, the level of understanding only you know. Few if any deaf start and tell the terp the degree of detail they can actually assimilate. Maybe they don't know themselves? hence why many terps tend to 'dumb down' to make things easier for some deaf to follow, details then get sketchy. Only one individual should be allowed to speak/sign at any one time and no 'side' comments are allowed, they have to be said one at a time so all are aware. Hearing don't do this, they will raise a point mid-explanation because they want clarification themselves, which can trigger response off others etc... Keep them on track!
The deaf meet has issues too, as it works mainly via 'Chinese whispers' in that the more able to follow deaf explain it to the next deaf person etc it is why you see signers at a meet apparently ignoring the speaker and getting an 'easier' explanation from the man or woman next to them. This, however, is fraught with issues if you are at the end of the line. You will note some who attend deaf meets have no real interest in what is going on, but, as with most of them, the social is the main event, so do not be surprised if they are discussing amid themselves the next deaf outing rather than what else the meet is for!
There is no real planning for a spontaneously raised issue. All you can do is ask for an explanation and its relevance to the main event. As with many meets, one response can lead to another, especially if clarifications are needed, you need to keep that in mind or lose perhaps the main point of a meet. If you are just going to attend and rely upon the terp to sort all that out, you will miss most. Of course, knowledge is power, so your hearing workmate may well keep the advantage it gives them. That's down to how you adjudge your friendship, do they always tell you what goes on? etc..
Hearing are in control, but only in as much as you allow it, unless being a spectator is your lot anyway.