I tried 3 simple checks , i am not sure if this is logical however i can send the sample files for you to test
1. downloaded the oracle table data from SQL Developer with less than 20 rows. this passed by bringing in the & to QV
2. downloaded the entire table dump which had close to 300k rows. this one failed with ampersand truncating the prefix.
3. from point 2, i copied the entire dump of data into a new sheet and just loaded the tab. this loaded the ampersand properly.
Can you tell me a best way to send the file, i am asking since these files would potentially contain data not to be available public. i prefer not to mask since this could potentially not help in reproducing the issue