UnShrunk SQL Server database restore which is larger than available disk space
I'm not sure if this is an answer, but it's too big to comment

I had the same issue many times. In my case it always was about the log file. when you get backup, the log file may not contain any active log/data and it will not take any space in the backup file, but when restoring, SQL server tries to allocate the same space. If there is any way you can ignore log file when restoring, you might be able to restore.

check this out, it may help