What HTML is
An HTML table is a table element containing thead and tbody, with th cells for headers and td cells for data.
Web pages, email templates and anything pasted into a CMS.
What BBCode is
BBCode uses square-bracket tags. Table support is not universal, but table, tr, th and td are widely implemented.
phpBB, vBulletin and forum software descended from them.
What changes when you convert HTML to BBCode
The first table in the markup is used. Cell contents are stripped of inline tags and entities are decoded, so <td><b>Total</b> </td> arrives as Total. Nested tables inside a cell are not descended into.
Check that your forum has table tags enabled. Many boards ship with them switched off.
What carries over from HTML to BBCode
HTML records 5 things about a table that BBCode has no way to hold.
HTML can hold a value that is itself a list or an object. BBCode has only flat cells, so nested values are flattened into one cell rather than being spread across columns.
A line break inside a cell ends the row in BBCode, so line breaks are replaced rather than carried through.
BBCode has no separate idea of a header, so the column names become an ordinary first row and nothing in the file marks them as different from the data.
Anything visual in the HTML - weight, alignment, colour, column widths - has no counterpart in BBCode and is dropped. The values are what survives.
BBCode is the end of the line for this data. Reading the table back out of it is a separate and much harder problem than writing it, so keep the HTML if you will need the values again.
The identifier 007 comes out of the BBCode as 007. Reading it as a number would have made it 7, and an id that changes value is worse than one that stays text.
The role "Analyst, data" survives with its comma, in one cell rather than split across two. That is the first thing to check in any converted table, and the usual place a BBCode file goes wrong.
The quotes around Jonah "Jo" Pryce are left as a plain quote character in the BBCode.