Not following the connection.
The two races you referenced provide a generic favored class, which is a consideration only for XP penalty (not always that much of a factor depending on the environment) and prestige class multiclass can negate much of that concern anyway. Humans get the extra skill point and feat. The only other advantage could be size, but small races gain AB, AC and better stealth and detection to compensate for the loss in unarmed damage. All medium races can DW kamas.
Don't see what any of that has to do with the advantages of using monk in a multiclass. Monk base saves are superior, but only when taken in pre-epic levels.
Yep, those two races get a generic favoured class. And yes, I'm talking about taking a monk level pre level 20.
However, what is important is that the list of abilities for monk at level 1 is awesome, and there is something there for just about everyone, except perhaps rogue, albeit certainly not bard or barbarian.
A druid/shifter that adds just one level of monk will get a substantial ac bonus from wisdom, and perhaps from the tumble skill. The cleave feat will not go remiss either. Nor the +2 on all saves.
A wizard/palemaster suddenly becomes a great deal tougher, again from ac, hitpoint and save benefits.
A cleric will gain from the cleave and evasion feats, and the +2 on saves.
In modules that revolve around stealth, the fact that move silent and hide are monk class skills, makes a non stealth specialist more viable.
Monks also gain persuade as a class skill, which makes the addition of monk to another combo usually a viable proposition.
In fact, the only module where I haven't found it useful, was in A Dance With Rogues. Here I stumbled upon what I found to be the best combo for that particular module imo. Went human rogue L1 for the skills. The intention was to be a good princess, but I didn't check the alignment shift as you 'recovered objects'. I started level 1 LG. Initial stats were S10, D14, C14, I14, W12, Ch14. I went Paladin L2, Rogue L3, Paladin L4 and Rogue L5. At level 6 my intention was to be a level 3 Paladin with the Divine Might feat. However, by this stage I was chaotic neutral, and Paladin was not an option. Further, I had 'wasted' 4 points on wisdom, to get a level 1 paladin spell at some point. Second time round I decided on good princess gone bad. I initially went Rogue 1, the went Paladin level 2 and 3, because immunity to fear is extremely useful both in part 1 and part 2. Didn't care about alignment and soon became chaotic evil, probably by Level 5, certainly by level 6. Then I went Blackguard, taking L3 BG at level 12, and BG L4 at Level 15 to get divine might and divine shield. Further, I didn't have to put 4 points into wisdom at level 1 and those I ended up putting into adding 2 points of dexterity (Stats: S14, D16, C10, I14, W8, Ch14. This proved a good call, since many thief skills rely on dexterity.
As I hope I've illustrated above, particular modules need to have tailored made PC's to win. Some don't. The range of abilities that a level 1 monk character brings to any build is truly remarkable.