BFing and Daycare- help please! (long)

FtrMrsC

I EBF but I have to return to work Monday.  DS started daycare last Wed. to get used to it before I went back full time.  We had been inconsistent about offering the bottle since I was a SAHM and able to nurse.  Now he won't take one.  The DCP tried and got him to take 2oz the first day(in 8hrs) but since then he won't take anything from the bottle when she offers it.

She told me the second day that she just ended up mixing 2oz with each of his solid meals he ate that day and mixing a little extra with some rice cereal later in the day.  So he took in 4oz in a 8hr day plus 2 solid meals.

The third day(Friday) he again refused the bottle and she was able to spoon feed him 2oz on two different occasions and also his solids.(again 4oz all day)  

I told her I would like her to keep trying with the bottle bc I'm worried that 4oz of BM isn't enough in a 8hr period.   I have tried to get him used to a sippy cup but he doesn't get much out of it either.  I think he isn't sure how it is supposed to work.

Lastly, I'm supposed to go out of town overnight for one night in 2 weeks (I'm MOH in a wedding in Vegas and DH refuses to take DS to Vegas) and my mom and aunt were going to watch DS.  Now I'm worried.  I don't want them to have to spoon feed him for 24hrs.  

Help!  Any advice would be great!