Lon, it looks like you are trying to make thoughtful and informed decisions for your company and clients. You are trying to do what's right, and not necessarily what is expedient or popular. I applaud that effort and I'd definitely want to hunt with someone like that, no matter what their ultimate policy decision was.
The Covid situation is dynamic and what was true today or 6 months ago may be invalid by the time the hunt starts. Six months ago, I wouldn't have cared if clients were not vaccinated. The vaccines had such effective sterilizing immunity against earlier, less contagious strains of the virus that the risk of even becoming infected if already vaccinated was minor.
Today, if I were in your place, I'd want my clients to have either been vaccinated or have a documented recovery from Covid. A very small number of people can't get vaccinated for medical reasons. If rapid Covid testing is available, that could also be used to screen for infection. If a positive showed, a follow-up PCR test could confirm. High air exchange indoors has been shown to reduce exposure. Weather permitting, perhaps I'd have meals and personal interaction outside. Simple changes and adjustments can be made to reduce infection risk. It doesn't have to be an always or never decision or policy. If the inconvenience is negligible for a sizable risk reduction, good tradeoff! If something is obtrusive/disruptive and you've already got other mitigations (like vaccination) in place, bad tradeoff!
Nothing is 100% and this silly, all-or-nothing binary thinking has created a real mess, causing people to rely on faulty intuition rather than reason. The barrage of "this vaccinated person got covid, see it doesn't work!" and "I wore a mask and got covid, masks don't work!" perfectly illustrates this. Would the same people argue that because a triathlete with only 5% body fat died of heart disease, exercise is pointless and being morbidly obese carries no extra mortality risk?
The chance of you or your staff becoming infected is reduced because of the vaccine. The chance of becoming severely ill is also reduced if you do become infected. Still, becoming ill would be disruptive to your business, even if symptoms are 'mild'. I think it is perfectly reasonable to make lots of small, unobtrusive changes to limit infection risk. I bet if the vaccine were in pill form, nobody would be freaking out about it, but needle = scary.