Silkie Princess
Crossing the Road
X2This sounds all very strange to me:
You already have a young dog (Talie) in your family. She was raised from puppyhood just fine.
And some weeks ago you started to look for a rescue for yourself. You tried several dogs and very abruptly said dogs were canceld within very short time.
Only days after bringing back the latest rescue dog to the shelter, you get the cutest puppy ever and after just one day/night he is on the "discarding list"?
I am sorry, but this all seems very wrong to me.
Get yourself a big enough dog transport box/dog kennel for the times you cannot be around.
Put him in there with his toys and blanket to make him comfortable. you can feed him in the kennel so he will associate the kennel with something good for him (a puppy his age needs 4 meals daily).
You can also get him used to sleep in the kennel at night and he will accept his kennel as a nice place for a nap or just relaxing.
ETA: Keep in mind the little guy is missing his mother and siblings very much, so he needs you to be around almost all the time. Have the kennel/crate at your bedside at night, so you will notice when he starts to whine and needs to go out to relieve hmself and he will not feel lonely and abondened with you next to him.