Using MPICH on two differnt architectures

Question

I am new to MPI. I am trying to get my x86 laptop and and a raspberry pi to "work together" via mpi. However I am having a hard time setting it up for the two to work together. I made a machinefile to store IP addresses. When I am running on the raspberry pi with only its IP in the machine file everything runs as expected, it is the same with the laptop. However when I have both IPs in the machine file nothing happens, I have to use ctrl+c to kill the command. On the laptop I am running slackware and on the raspberry pi raspbian.

Here is what I get when i run mpiexec --version

# raspberry pi###############
HYDRA build details:
    Version:                                 3.4.1
    Release Date:                            Fri Jan 22 14:17:48 CST 2021
    CC:                              gcc -Wdate-time -D_FORTIFY_SOURCE=2 -g -O2 -ffile-prefix-map=/build/mpich-a7gXGS/mpich-3.4.1=. -fstack-protector-strong -Wformat -Werror=format-security  -Wl,-z,relro
    Configure options:                       '--with-hwloc-prefix=/usr' '--with-device=ch3' 'FFLAGS=-O2 -ffile-prefix-map=/build/mpich-a7gXGS/mpich-3.4.1=. -fstack-protector-strong -fallow-invalid-boz -fallow-argument-mismatch' '--prefix=/usr' 'CFLAGS=-g -O2 -ffile-prefix-map=/build/mpich-a7gXGS/mpich-3.4.1=. -fstack-protector-strong -Wformat -Werror=format-security' 'LDFLAGS=-Wl,-z,relro' 'CPPFLAGS=-Wdate-time -D_FORTIFY_SOURCE=2'
    Process Manager:                         pmi
    Launchers available:                     ssh rsh fork slurm ll lsf sge manual persist
    Topology libraries available:
    Resource management kernels available:   user slurm ll lsf sge pbs cobalt
    Demux engines available:                 poll select
    

# Slackware
mpiexec (OpenRTE) 4.1.0

Report bugs to http://www.open-mpi.org/community/help/

the command I am running, on slackware, is

mpirun --hostfile machinefile -np 2 hostname

I want the laptop to be like a head for multiple raspberrys. I Imagined that since mpi is a standard I would be able to get these two versions to communicate without much of a hassle. Is there something I need to configure to get these two computers to work?

Thanks for your time