failing bash variable matching

I have been driving myself mad on this. I just don't see why it doesn't work when bash variables are untyped. There should be no reason why not.

pat1=`. $NVM_DIR/nvm.sh && nvm ls | sed 's/\x1b\[[^\x1b]*m//g' | sed -e 's/[[:alpha:]|\/\)\-\>\(|[:space:]]//g' | sed 's/[-|\*]//g' | sed '/^$/d'`
pat2=`. $NVM_DIR/nvm.sh && nvm ls node | head -1 | awk '{print $2}' | cut -d v -f2`

these expand to:

~$ echo $pat1
9.5.0
9.5.0
9.5
9.5.0
4.8.7
6.12.3
8.9.4

~$ echo $pat2
9.5.0

So I want to check if the string found in $pat2 is in $pat1 string. however it does not find it even though it clearly is in the pattern 3 times at least.

Checking for the pattern with a test like:

case "$pat1" in
  *$pat2*) 
    echo 'match'
    ;;
  *)
    echo 'nomatch'
    ;;
esac

this gives:

~$ ./test.sh 
nomatch

another test:

if [[ "$pat1" =~ "$pat2" ]]; then 
  echo 'match'
else 
  echo 'nomatch'
fi

again fails:

~$ ./test.sh
nomatch

Even tried some janky hacky method to no avail,

echo $pat1 | grep "$pat2" > /dev/null 
if [ $? -eq 0 ]; then
  echo "matched"
else
  echo "nomatch"
fi

gives the result:

~$ ./test.sh
grep: brackets ([ ]) not balanced
nomatch

Been pulling my hair out today working on this. This must be due to the fact that both variables are command substitutions, it leads me to believe it is comparing the actual commands themselves rather than their output stored in the variables. So even though they echo the output, i think it may be comparing the string of the commands itself.

am I wrong? can anyone explain why this fails to match and if its possible with bash to compare the output of two commands in a string/sub-string type of comparison?