The Wildcats (4-5, 1-0) erased an early 10-0 deficit, closing the first half on an 18-7 run to take a four-point lead into the break. Senglin hit two 3-pointers to help push that lead to 58-47 at the 11:49 mark.
Eastern Washington (5-7, 0-1) cut their deficit to three after a Venky Jois layup with 1:42 remaining, but Jois was blocked by Bolomboy on the ensuing possession.
Bolomboy and Jordan Richardson each sank a pair of free throws in the final minute to cap the scoring.
Weber State shot 48.1 percent from the field. Kyle Tresnak had 13 points and seven boards for the Wildcats.
Tyler Harvey led the Eagles with a career-high 30 points and Jois added 14 with seven rebounds.