Thanks for your post and the update!
Your update was right in line with what I would have offered as a solution. You mentioned the client uses Version 7 QS for their needs.
But since QS is just an .exe, you can still have them run your Version 13 QS so that you can connect when needed. And they can continue using their Version 7 after you have disconnected.
I might also recommend the client company using Version 7 QS use a fresh copy of version 7 QS which can be found at the link below.
Let me know if this helps,
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