How to print the error of a system call in R - r

Question

I'm attempting to use the system function in R to run a program, which I expect to yield an error message in some cases. For this I want to write a tryCatch function.
system(command, intern = TRUE) only returns the actual values which were echo'd by the program I'm running, it does not return my error.
In R, how can I get the error message which was yielded by my system?
My code:
test <- tryCatch({
cmd <- paste0("../Scripts/Plink2/plink --file ../InputData/",prefix," --bmerge ",
"../InputData/fs --missing --out ../InputData/",prefix)
print(cmd)
system(cmd)
} , error = function(e) {
# error handler picks up where error was generated
print("EZEL")
print(paste("MY_ERROR: ",e))
}, finally = {
print("something")
})
[1] "../Scripts/Plink2/plink --file ../InputData/GS80Kdata --bmerge ../InputData/fs --missing --out ../InputData/GS80Kdata"
PLINK v1.90b3.37 64-bit (16 May 2016) https://www.cog-genomics.org/plink2
#....
#skipping some lines here to reduce size
#....
Of these, 1414410 are new, while 2462 are present in the base dataset.
Error: 1 variant with 3+ alleles present.
* If you believe this is due to strand inconsistency, try --flip with
# Skipping some more lines here
[1] "something"
However when using intern=TRUE and assigning the system function to a variable won't catch the error in the vector and still prints it in the R console.
Edit: Here the output of the vector (using gsub to reduce the ridiculous size)
> gsub(pattern="\b\\d.*", replacement = "", x = tst)
[1] "PLINK v1.90b3.37 64-bit (16 May 2016) https://www.cog-genomics.org/plink2"
[2] "(C) 2005-2016 Shaun Purcell, Christopher Chang GNU General Public License v3"
[3] "Logging to ../InputData/GS80Kdata.log."
[4] "Options in effect:"
[5] " --bmerge ../InputData/fs"
[6] " --file ../InputData/GS80Kdata"
[7] " --missing"
[8] " --out ../InputData/GS80Kdata"
[9] ""
[10] "64381 MB RAM detected; reserving 32190 MB for main workspace."
[11] "Scanning .ped file... 0%\b"
[12] "2%\b\b"
[13] "%\b\b"
[14] "\b\b"
[15] "\b"
[16] ""
[17] "58%\b\b"
[18] "7%\b\b"
[19] "%\b\b"
[20] "\b\b"
[21] "\b"
[22] "Performing single-pass .bed write (42884 variants, 14978 people)."
[23] "0%\b"
[24] "../InputData/GS80Kdata-temporary.bim + ../InputData/GS80Kdata-temporary.fam"
[25] "written."
[26] "14978 people loaded from ../InputData/GS80Kdata-temporary.fam."
[27] "144 people to be merged from ../InputData/fs.fam."
[28] "Of these, 140 are new, while 4 are present in the base dataset."
[29] "42884 markers loaded from ../InputData/GS80Kdata-temporary.bim."
[30] "1416872 markers to be merged from ../InputData/fs.bim."
[31] "Of these, 1414410 are new, while 2462 are present in the base dataset."
attr(,"status")
[1] 3
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