Frustrated

My fiance and I booked our venue for our rehearsal dinner at the beginning of the year. We were under the impression 33 people would be attending our bridal party and their dates, my parents, his father and father's fiancee, his mother and mother's plus one, my grandmother (she is our reader) and grandfather on my mom's side, and our 2 flower girls, 1 ring bearer, 1 usher, and their parents (flower girls, ring bearer and usher are siblings). My venue is supposed to be calling us in about 2-3 weeks to confirm number of people attending. They require a minimum of 30 people. I already knew everyone on my side was attending, but my fiance never asked anyone on his side about it. I reached out to his groomsmen/groomsman and his parents. His mother isn't bringing a date and his father and father's fiancee can't attend because his father has to work. I thought my fiance mentioned to his father about the rehearsal, but after talking his father's fiancee it appears he didn't. His one groomsman will likely not be attending. Everyone else in our bridal party believed it was mandatory for them to attend and I tend to agree. His groomsman has known about the wedding and rehearsal for about 10 months. I don't have the groomsman's cell phone number so I was asking his wife about it and she said he has to work which I understand, but I asked her what time he works until and she completely ignored that question. I believe she said before he normally works 7 am - 3 pm. Our rehearsal is at 4:30 pm so work shouldn't interfere with him attending, but if she had confirmed what time he worked we would have gladly tried to accommodate him. Instead, his wife expressed that they aren't comfortable leaving their baby for an entire weekend. Unfortunately, due to numbers and our budget we could not include children at the wedding. If they don't want to leave the baby that is fine. They could bring the baby to the rehearsal because we have no problem with the baby attending rehearsal. They could also bring a babysit with them or his wife could stay home with the baby. The wife's sister lives with them so she might even be able to watch the baby while they are at our rehearsal or either of their mothers could watch the baby. My feelings are that the groomsman should've told us as soon as he knew that he couldn't attend. I think it is rather rude of him to avoid calls and text messages about the bachelor party as well.