Moses unable to enter the tabernacle at all, the glory too overwhelming -- the exact problem Leviticus exists to solve.
Yahweh called to Moses, and spoke to him from the Tent of Meeting, saying,
Moses wasn’t able to enter into the Tent of Meeting, because the cloud stayed on it, and Yahweh’s glory filled the tabernacle.
Leviticus is built as a symmetrical, book-length structure around one center. Rituals for approaching God open the book (ch.1-7) and close it again in a different form, the annual feasts (ch.23-25). Inside that: the priesthood's ordination (ch.8-10) and, mirroring it, the standards priests must live by (ch.21-22). Inside that again: ritual purity (ch.11-15) and moral purity (ch.18-20). And at the very center, holding the whole design together: the Day of Atonement (ch.16-17) - the one ritual that covers whatever the rest of the system doesn't catch.