Both sides played their part in an entertaining match which the home side will benefit from as they progress to the latter rounds of the Dewar Shield.
Two tries from Will Van Klaveran kept the Exiles in the match and a late score from Tom Griffiths reflected a strong finish from the visitors.
Welsh Exiles Secretary Terwyn Williams was pleased with his side's performance saying afterwards: " I was delighted with the commitment and endeavour of the Exiles side against a very strong 'Islwyn' team who are one of the strongest in Wales.
"Despite having very little preparation time this was an excellent team effort. Nevertheless, we are still disappointed with the defeat but look forward to seeing these boys representing the Exiles again".
Welsh Exiles Under 15s Squad: Nick Bloom, Kings, Wimbledon; Dylan Sutton, Chiselhurst & Sidcup, Kent; Tom Griffiths, Churchdown School, Gloucestershire; Charlie Williams, Kings, Wimbledon; Alex Price Richards, St. Barts, Newbury; Will Van Klaveran, Kings, Wimbledon; Allen Crawshaw, Claires Court, Berkshire; Alex Griffith Jones, Hampton, Middlesex; Josh Crawford, Trinity, Leamington; Charlie Murphy, Eltham College, Middlesex; Ben Snowden, Arnold Hill, Nottinghamshire; Will Foster, Eltham College, Middlesex; Lewis Lloyd, Desborough, Berkshire; Jack Rogers, Redborne, Bedfordshire; Edward Hatcher, John Fornally College, Melton Mowbray; Cole Bates, St. Barts, Newbury; Connor O'Neill, Sandy, Bedfordshire; Simon Graham, John Hampton, High Wycombe; Christian Holland, Queen Elizabeth, Bristol; Jason Richards, Therfield, Middlesex.