Rest of AppleScript is ignored when I use a variable in posix path - variables

Question

I'm using AppleScript in Automator to copy a page's source and save it to a file. For some reason when I use a variable (titleVal) in the posix path, the rest of my code in my loop is ignored, including the file that never gets written.
I updated the code before with my full AppleScript in case it has to do with more than the few lines I had before. I'm using Automator with specified Finder items in this order: "urlList.txt" and fileList.txt".
on run {input, parameters}
set updateCount to 0
read (item 1 of input)
set ps to paragraphs of the result
set tot to count ps
set TLFile to (("Users:Admin:Desktop:download captions:") as text) & "fileList.txt"
set TLLines to paragraphs of (read file TLFile as «class utf8»)
tell application "Safari"
reopen
activate
end tell
repeat with i from 1 to tot
set p to item i of ps
if p is not "" then
try
tell application "Safari"
tell front window
set r to make new tab with properties {URL:"https://www.youtube.com/timedtext_editor?v=" & p & "&lang=en&name=&kind=&contributor_id=0&bl=vmp&action_view_track=1"}
set current tab to r
set titleVal to item i of TLLines
set updateCount to updateCount + 1
do shell script "echo The value: " & updateCount
delay 2
do JavaScript "document.getElementById('movie_player').outerHTML = ''" in current tab
do JavaScript "document.getElementById('creator-page-sidebar').outerHTML = ''" in current tab
do JavaScript "document.getElementById('footer').outerHTML = ''" in current tab
delay 3
do JavaScript "document.getElementsByClassName('yt-uix-button yt-uix-button-size-default yt-uix-button-default action-track-button flip yt-uix-menu-trigger')[0].click()" in current tab
delay 1
do JavaScript "document.getElementById('aria-menu-id-2').getElementsByTagName('ul')[0].getElementsByTagName('li')[5].getElementsByTagName('a')[0].click()" in current tab
delay 4
-- using a variable in path1 is where it screws up. try changing it to another variable value and it will have the same effect.
set myString to source of current tab
set path1 to "/Users/Admin/Desktop/download captions/downloadedCaptions/" & titleVal & ".srt"
say path1
set newFile to POSIX file path1
--set newFile to POSIX file "/Users/Admin/Desktop/download captions/downloadedCaptions/test.xml.srt"
open for access newFile with write permission
write myString to newFile
close access newFile
-- i have exit repeat here to only test the first loop
exit repeat
end tell
end tell
end try
end if
end repeat
end run
Without a variable works fine, but I need the variable to make the script work properly in a loop. I've checked the value of the var. I also tried "& quoted form of titleVal &".
Update: When I remove the try/end try as suggested to get the error, the error is:
The action “Run AppleScript” encountered an error: “Safari got an error: Can’t get POSIX file "/Users/Admin/Desktop/download captions/downloadedCaptions/test.srt" of window 1.”

Answer 1

The error occurs because you are going to write the file in the tell window block of Safari which cannot work.
I recommend to use a separate handler. Put the on writeFile handler outside of the on run handler. I added reliable error handling and the data are saved UTF-8 encoded.
on writeFile(theData, fileName)
set newFile to "/Users/Admin/Desktop/download captions/downloadedCaptions/" & fileName & ".srt"
try
set fileDescriptor to open for access newFile with write permission
write theData to fileDescriptor as «class utf8»
close access fileDescriptor
on error
try
close access newFile
end try
end try
end writeFile
and call it (replace the part of your code from delay 4 to the end)
delay 4
-- using a variable in path1 is where it screws up. try changing it to another variable value and it will have the same effect.
set myString to source of current tab
my writeFile(myString, titleVal)
exit repeat
end tell
end tell
end try
end if
end repeat
end run

Answer 2

This was fixed very easily by changing one line:
set newFile to POSIX file path1
to:
set newFile to (path1 as POSIX file)
But I don't know why. Seems like a bug since it worked without the variable. Please provide any details in the comments why this works over the original set newFile line.