Hello - Hi - I need to book a tickettoday for a colleague travelling from Cairo to London on BA in 3 days time, and want to be 100% I get the names correct in terms of booking the ticket so it matches the ATC system so he shows as "OK to board"

He has four names in total, and I want to book his ticket using the correct given (first) name and the correct surnames

The machine readable line on his passport shows PCSDN NAME1<NAME2<NAME3<<NAME4<<<<<<<<<<<<<<<<

i know that he uses <<NAME4 as his first name - so am I correct to enter that as his first name and other three as surnames?

His UKVI skilled worker visa always addresses his as Mr NAME4 NAME1 NAME2 NAME3 NAME4 on his Visa - but my understanding is that when the visa was granted a few weeks ago the home office will have sent the machine readable line to the ATC system (i.e. PCSDN NAME1<NAME2<NAME3<<NAME4<<<<<<<<<<<<<<<<) which means if I use that for BA then it will be correct.

Apologies if this is something that's obvious, but after four months of more paperwork and processes than I've ever gone through in my life I want to make 100% sure I book the ticket correcly - and thanks in advance for any info on this question.