Over the weekend, I installed approximately 700 ft² of US Floors strand woven floating bamboo floor. (EXCELLENT product, by the way. ZERO waste to speak of, other than my errors). However, under a large doorway between kitchen and living room, there is an area that feels "spongy". It's obviously due to me not getting my subfloor level in that spot. (IDIOT!) It's maybe 2 feet wide, and runs perpindicular to the boards about 6 feet.
It's a "drop n lock" install, not T&G.
To tighten it up, I plan on cutting and removing one board (hopefully not more) and sliding maybe real thin plywood under the 3 in 1 underlayment in this area, with hopes that it will take the flex out of the bamboo, then reinstalling and gluing the bamboo board back.
Does this seem like a viable option from here? Obviously, there are a lot of "should haves" but it's too late to tear up the floor and start again.
Thanks for any and all advice.