Help With Secret Sacristy rm 15538

[Corpus]

I've explored the Secret Sacristy upper and lower but I do not have a blue key for the lower doors,(Rooms 15537 and 15538), are there any blue keys in this area? I have one purple key left .
Any help would be appreciated Including e-mailing me a spoiler so as not to ruin it for others.


Thanks, Awesome work.