Can you post the output of SELECT @@VERSION please?
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Has anything changed since you last ran the backup job, i.e. CU applied etc?

Quick suggestion, have a look at these two articles, Tally OH! An Improved SQL 8K “CSV Splitter” Function and Reaping the benefits of the Window functions in T-SQL

For fun, here is a more efficient way (I think 😉 not tested) 
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This should get you passed this hurdle
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USE TEEST;
GO
SET NOCOUNT ON;

DECLARE @TXML XML = '<root>
<v_R_System>
<ResourceID>33558284</ResourceID>

This can be simplified with the concat function.
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USE TEEST;
GO
SET NOCOUNT ON;

DECLARE @PERC DECIMAL(6,4) = 1.25;

SELECT CONCAT(CONVERT(INT,@PERC...

Can you post the queries and the execution plans?
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