Em man bash
:
Aliases are not expanded when the shell is not interactive, unless the expand_aliases shell option is set using shopt.
Então, eu acho que você precisa adicionar shopt expand_aliases
no seu script bash
.
Teste:
$ cat 1.sh
#!/bin/bash
alias ll='ls -l'
ll $HOME
$ ./1.sh
./1.sh: line 3: ll: command not found
$ cat 2.sh
#!/bin/bash
shopt -s expand_aliases
alias ll='ls -l'
ll $HOME
$ ./2.sh
total 12
...