As with everything ... we go by 2 guiding principles that are synergistic :
1) Realism
2) K.I.S.S.
Chances are if you were in them military or an outdoorsman, hunter, etc. you may have a pretty good idea how LOS, cover & concealment, camo, terrain masking and blocking, etc. works.
Terrain in the Army is broken down into 3 basic types:
1) Closed
2) Open
3) Mixed
E.g. Closed would be jungle, forests, urban ...
Open - pretty obvious
Mixed - " "
Cover is something solid that could stop all the bullets, shrapnel, fragmentation, secondary missiles[i.e. debris from explosions, etc.], etc.
Concealment limits or breaks LOS, but is not solid. E.g. foliage, crops, hedges, tentage, etc. It won't stop much of anything save for blocks LOS. Which as camo does makes targets harder to hit.
Some maybe for just the "exercise", some might want to go outside and check out how LOS, ranges, etc. actually works. Again, maybe just to clear some of your doubts up.
But again [try] to keep your conclusions guided by :
1) Realism
2) K.I.S.S.
And remember wargaming isn't [or shouldn't be]"rocket science" ... and realism & K.I.S.S. are or should be synergistic. I've been playing wargames since the '60s, including 1 to 1 scale for a over a decade in the '80s. I've been around the block a few times and saw a number of ways to do things on gaming board or table. And in actual on the ground/hands on experience. But as always do what works for you. Not me ...
Now based on all the pics just posted. All but the last the target should get cover. Also the way SM1 did it and we did it, because it is realistic, Infantry that is not moving[based on orders] gets cover. As Infantrymen usually get prone to make themselves a smaller target, etc. When not moving, or crouched down when moving. And tries to use every fold, bump, log, etc. to give some cover and/or break LOS.
Now in the pics moving or not they get cover, as there is terrain of some type between them and the AFV. And vis versa. In a firefight/combat everybody/thing tries to get something solid between them and incoming fire. And if not, something to break or block LOS.
The last pics LOS is blocked.