I never doubt the quality of Kyle Walker, but I don't think Bayern Munich will sign him. If they transfer, it would be a good challenge for Walker, of course. I think he will go to Saudi Arabia to earn money because a 33-year-old football player will want to earn serious money in his last days.
At that age it's time to think about money over career and I think that's also a very natural thing for him, but if there is still an option for a better team in a more popular league I don't think Kyle Walker would be wrong to go there either. But in this case I agree more that Kyle Walker wants to consider more money than continuing his career which will eventually be released by the team that signed him at that age.
This is a normal trend with football stars and it's quite knowing that you staying in your previous club will not do you any good because the space for younger players will always surface and the manager will likely start a younger vibrant player than walker so choosing a career base on the financial benefits is better probably to stand to the fact that you want to experience good football.