I will agree with you, that we do need to ask why the access lid opens in this fashion. There is a design purpose and I don't think it is connected to a VLS system and more like an access panel to the back side of the thermal management system or just tool storage. This hatch/access panel appears to be manually operated versus a actuator operated fashion.Considering the current variety of top attack munition and the fragments that may be produced by APS intercepting them, this can an additional protection for VLS units. This is something that the Navy VLS does not have to face.
If this is just the access panel hatch, then we have to ask why only the Type 100 support vehicle has this hatch design that is both upward and inward facing. Compared to pure armor plate, this is a clear structural disadvantage in terms of protection.
Where is the information that this is VLS system, I must have missed the forum post that the PLA or Norinco was working on a vehicle mounted VLS system.
Bottom line is that I think this is not a VLS system, but I can be wrong and you can be right. At the moment the indicators of this hatch/access panel do not suggest a VLS system.