it’s only for a couple of hours a Dog Walker would solve the whole thing, but it seems OP has disengaged anyway so no need for any angst.
As per the opening post, it wasn't going to be a couple of hours, her DB wanted to come overnight ... which a dog walker would not solve.
Equally, why should the OP have to pay for a dog walker to accommodate a visitors demands?
I personally think having a kennels the dog now sand is comfortable in is part of very basic dog care.
I don't disagree that it is good to have somewhere other than the family home which a dog is comfortable at, but it does not need to be kennels. My parents dog is occasionally boarded at a local kennels and she loves it, but that doesn't mean that my parents are obliged to send her there every time they go away. I'm currently petsitting for them because to put the dog in kennels while they were away for 3 weeks over Christmas would have cost almost £2k ... having me petsit has cost them practically nothing - the dog is comfortable at my flat for overnight stays but for 3 weeks it was easier for me to stay at my parents.
I also think accommodating people’s, but especially families and probably more so family children needs is the least I would attempt to do.
If I invite someone to my house then I will do everything within my power to accommodate them, but there are limits - including kicking my pets out of their home for over 24hrs - and if it is going to cost me significant amounts of money then it is my perogative to decide how much I can afford to pay out in accommodations before if becomes an impossible situation.
Equally, if someone invites themselves then I will do what I can but I am under no obligation to make any accommodations for their visit - for example, if the OPS DB wanted to visit when she was on holiday, she would not be obliged to rearrange her holiday or allow him into her house without her there just because he wanted to visit at that time.
OP is asking if she should be more accommodating, I think she should (because that’s what I would do)
Considering that her DB invited himself and was making unreasonable demands beyond the accommodations that the OP can/was willing to offer then I disagree. She has no obligation to accommodate someone she didn't invite.