How to pass parameter expansions into qsub?

Question

I'm trying to use qsub to submit multiple parallel jobs, but I'm running into trouble with passing parameter substitutions into qsub. I'm using the -V option, but it doesn't seem to recognize what ${variable} is. Here's some code I tried running:

qsub -cwd -V -pe shared 4 -l h_data=8G,h_rt=00:10:00,highp -N bt2align3 -b y "projPath="$SCRATCH/CUTnTag/data_kayaokur2020"; sample="K4m3_rep1"; cores=8; 
bowtie2 --end-to-end --very-sensitive --no-mixed --no-discordant --phred33 -I 10 -X 700 
-p ${cores} 
-x ${projPath}/bowtie2_index/GRCh38_noalt_analysis/GRCh38_noalt_as 
-1 ${projPath}/raw_fastq/${sample}_R1.fastq.gz 
-2 ${projPath}/raw_fastq/${sample}_R2.fastq.gz 
-S ${projPath}/alignment/sam/${sample}_bowtie2.sam &> ${projPath}/alignment/sam/bowtie2_summary/${sample}_bowtie2.txt"

I just get an error that says "Invalid null command."

Is qsub not able to recognize parameter expansions? Is there a different syntax I should be using? Thanks.