Thanks for linking to your January question.
Before you get too concerned, I will repeat my earlier point (last January) that children develop at different rates and in different areas, so this may still not be a matter for concern.
I'd make sure that your child's hearing and eyesight are in the normal range. Children can't tell us they aren't hearing/seeing as well as they should, because they don't know and they cope better than we might think. I am not saying this is the problem, just suggesting that you check.
- "The boy didn't respond to teacher or other boys's greetings"; He might be shy or have had a scare from another child that makes him reticent. If you or Mother can help model greetings at daycare and in other suitable groups, it may help. If you can join a group on weekends for parents and children (swim lessons, tumbling, music...) that would be a good place for you to help and to observe what is happening.
- "The boy didn't follow teacher's instructions, sometime just repeat what the teacher says." This could be the language barrier, shyness, fear of making a mistake, or a lack of understanding of the instructions. Try giving your child choices at home and praising him for his making them and for anything he does that is praiseworthy.
- "Sometime he invades into other toddlers' playing space" This is absolutely what toddlers do -- don't worry about it unless it is hitting or biting.
- "Other than the social skill concerns, the boy is very smart and sensitive to words, numbers, colors and shapes." Great!
- "The teacher said the township mandates that toddlers be evaluated if they have a concern about his social skill at the age of 3 or older." Please do not look at this as a negative. It is a pro-active way to get your son help if he needs it. An evaluation won't make him anything or give him a problem. IF there is a problem, earliest possible intervention is your best option.
You say you are concerned about the two languages. I would not change a thing unless a medical professional suggests you should. Having multiple languages is a gift that opens a world of options to your son.
You say you are concerned that you pamper your son too much. (IMO, you can't spoil children, but) You do need to discipline and give consequences for naughty behaviours. Simply make sure your son understands why you are giving him a consequence because if he doesn't understand, it is pointless.
You should be giving your son choices and allowing him to live with the consequences. If you need help with introducing choices, I can help.